Class 


Book 


L-IBRKRV 

OF  THE 

MEDICAL  DEPARTMENT, 


TULANE  UNIVERSITY  OF  LOUISIANA 

PRESENTED  BY 

/ 


THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 

PRESENTED  BY 

PROF.  CHARLES  A.  KOFOID  AND 
MRS.  PRUDENCE  W.  KOFOID 


ELEMENTS 


GENERAL  ANATOMY, 


- 

OR, 


A  DESCRIPTION  OF  EVERY  KIND  OF  ORGANS  COMPOSING  THE 
HUMAN  BODY. 


P.  A.  BECLARD, 

PROFESSOR  OF  ANATOMY  OF  THE  FACULTY  OF  MEDICINE  OF  PARIS. 

• 

Preceded  by  a  Critical  and  Biographical  Memoir  of  the  Life  and  Writings  of 

the  Author, 

BY  OLIVIER,  M.  D. 
TRANSLATED  FROM  THE  FRENCH,  WITH  NOTES, 

BY  JOSEPH  TOGNO,  M.  B. 

MEMBER    OF     THE     PHILADELPHIA     MEDICAL     SOCIETY. 


CAREY  AND  LEA. 

1830. 


/ 


I 


Eastern  District  of  Pennsylvania,  to  wit: 

BE  IT  REMEMBERED,  that  on  the  twentieth  day  of  October,  in  the 
fifty -fifth  year  of  the  Independence  of  the  United  States  of  America,  A.D. 
1830,  Carey  &  Lea  of  the  said  district  have  deposited  in  this  office  the 
title  of  a  book,  the  right  whereof  they  claim  as  proprietors  in  the  words 
following,  to  wit: 

*'  Elements  of  General  Anatomy,  or,  a  description  of  every  kind  of  organs 
composing  the  human  body.  By  P.  A.  Beclard,  Professor  of  Anatomy  of 
the  Faculty  of  Medicine  of  Paris.  Preceded  by  a  critical  and  Biographical 
Memoir  of  the  Life  and  Writings  of  the  Author,  by  Olivier,  M.  D.  Trans- 
lated from  the  French,  with  notes,  by  Joseph  Togno,  M.  D.  Member  of 
the  Philadelphia  Medical  Society." 

P 

In  conformity  to  the  Act  of  the  Congress  of  the  United  States,  entitled 
"An  Act  for  the  encouragement  of  learning,  by  securing  the  copies  of 
maps,  charts,  and  books  to  the  authors  and  proprietors  of  such  copies 
during  the  times  therein  mentioned;" — And  also  to  the  Act  entitled  "  An 
Act  supplementary  to  an  Act  entitled  « An  Act  for  the  encouragement  of 
learning  by  securing  the  copies  of  maps,  charts,  and  books  to  the  authors 
and  proprietors  of  such  copies  during  the  times  therein  mentioned,'  and  ex- 
tending the  benefits  thereof  to  the  arts  of  designing,  engraving,  and  etching 
historical  and  other  prints." 

D.  CALDWELL, 
Clerk  of  the  Eastern  District  of  Pennsylvania. 


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THE   MEMORY 


BICHAT,  BECL.ARD, 


THE  TRANSLATOR. 


THE  TRANSLATOR'S  PREFACE. 


The  task  of  the  translator,  although  very  confined,  is  not 
altogether  unimportant  to  the  advancement  of  the  arts  and 
sciences,  and  especially  to  the  improvement  of  the  medical 
science  in  this  country,  at  this  present  time. 

Forbidden  to  add  to,  or  to  subtract  from  the  original,  the 
translator's  business  is  simply  to  interpret  and  translate  his 
author's  meaning  faithfully,  and  to  render  it  in  clear  and  in- 
telligible language. 

It  has  been  the  fate  of  the  translator  of  the  present  work,  to 
give  an  English  version  of  the  last  labours  of  the  lamented 
Bichat;  and  now,  again,  the  ten-fold  more  difficult,  but  pleas- 
ing task  devolves  on  him,  of  presenting  to  the  medical  profes- 
sion of  this  country,  the  last  work  of  the  eminent,  erudite,  and 
much  lamented  Beclard. 

The  object  of  the  translator  will  be  fulfilled,  and  he  will  be 
repaid  for  his  trouble,  if  without  deviating  from  his  author, 
he  has  made  the  original,  clear  and  comprehensible  to  his 
English  reader.  But  should  some  stern  critic,  eager  to  find 
fault,  censure  the  performance,  which  has  cost  the  trans- 
lator much  labour,  trouble  and  solicitude  ;  and  under  circum- 
stances that  the  reader  is  seldom  solicitous  to  know,  and  sel- 
domer  inclined  to  make  due  allowance  for ;  let  him  remember, 
that  if  this  English  version  is  not  faultless,  still  much  has  been 


VI 


done  to  render  it  worthy  of  the  approbation  of  the  profession. 
Indeed,  I  may  well  be  contented,  without  claiming  for  this 
translation,  the  praise  of  perfection,  while  I  daily  witness 
similar  attempts,  coming  from  higher  sources,  not  altogether 
exempt  from  errors. 

For  instance,  since  the  greater  part  of  this  version  has  been 
printed,  we  have  had  in  our  hands  the  translation  of  the  same 
work  by  Dr.  Knox  of  Edinburg,  well  known  to  the  medical 
profession  as  a  writer  and  a  lecturer.  We  opened  this  volume 
by  chance  in  many  places,  and  we  have,  not  without  great  sur- 
prise, found  some  very  gross  errors.  We  will  point  out  some 
of  them,  not  to  gratify  malice  or  jealousy  on  our  part,  but 
merely  to  show  that  the  faithful  and  correct  performance  of  a 
translation,  is  not  as  easy  a  task  as  some  critics  would  make  us 
believe.  Should  we  ourselves  have  fallen  into  errors,  not- 
withstanding all  our  care  and  attention  to  produce  a  faultless 
translation,  we  wish  thereby  to  show,  that  we  are  entitled  to 
some  indulgence  from  our  reader. 

Dr.  Knox  points  out  one  single  error  in  his  erratum,  and 
we  turned  to  the  page  indicated ;  on  reading  the  same  para- 
graph, we  found  just  above  the  error  alluded  to  the  following 
sentence,  which  we  shall  give  with  the  original,  and  opposite  to 
our  own  version.  This  induced  us  to  look  cursorily  into  the 
book,  and  to  our  great  astonishment,  we  found  such  errors,  in 
point  of  science,  as  made  us  rather  tremble  for  the  performance 
of  the  other  parts  of  the  work.  We  shall  here  quote  some  of 
the  principal  blunders  committed  by  Dr.  Knox,  for  the  edifica- 
tion of  our  readers. 


THE  TRANSLATOR'S  PREFACE. 


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We  ought  to  say  a  few  words  in  commendation  of  the  ori- 
ginal work  of  Beclard;  but  we  believe  its  merits  so  well 
known  that  we  shall  dispense  ourselves  from  dwelling  on  them. 
However,  we  know  that  there  exists  yet,  among  some  of  the 
younger  members  of  the  profession,  a  very  false  and  errone- 
ous idea  of  what  GENERAL  ANATOMY  really  means.  In  order 
to  elucidate  this  subject,  we  shall  extract  the  following  excel- 
lent explanatory  passage  from  a  Lecture  of  Dr.  Godman  on 
General  Anatomy. 

"  We  have  in  the  outset  to  regret  that  the  use  of  a  term  should 
have  led  to  misapprehension  among  some  of  the  members  of 
our  profession,  who  from  the  title  General  Anatomy,  have  re- 
ceived an  impression  that  it  is  nothing  more  than  a  general 
outline,  or  sketch  of  common  or  special  anatomy,  stripped  of 
its  minuteness. 

"  Such  an  idea  of  General  Anatomy  is  totally  erroneous,  and 
has  in  some  instances  led  to  the  most  injurious  neglect  of  pre- 
cious knowledge.  General  anatomy  is  the  science  of  organi- 
zation, not  of  individual  organs.  It  teaches  the  elementary 
textures  composing  all  the  parts  of  the  body  without  reference  to 
the  specific  structures  they  aid  in  forming.  In  this  sense  alone, 
it  is  general,  but  in  the  determination  of  the  qualities  and  laws 
of  the  elementary  textures,  and  of  the  manner  in  which  these 
are  linked  together,  this  science  is  most  minute,  precise,  and 
definite,  bringing  us  into  the  most  intimate  acquaintance  with 
the  entire  economy  of  the  system,  and  breaking  down  the  bar- 
riers which  the  habit  of  exclusively  studying  special  organs, 
invariably  raises  around  us. 

"  General  Anatomy,  then,  is  not  descriptive  or  Special  Ana- 
tomy in  outline,  but  the  anatomy  of  elementary  textures,  of 


THE  TRANSLATOR'S  PREFACE.  xi 

minute  organization  without  reference  to  form  or  place.  It 
is  to  Anatomical  science  what  Chemistry  is  to  the  other  branch- 
es of  natural  science.  Whatever  may  be  the  texture  examined, 
it  is  considered  in  all  aspects,  and  throughout  every  modifica- 
tion, whether  it  be  found  in  the  substance  of  tendon,  muscle, 
ligament  or  bone.  All  its  qualities  are  sought,  the  distinctive 
characters  established,  and  the  laws  of  its  susceptibilities  and 
actions  deduced  from  the  amplest  experiments  and  observa- 
tions.'' 

October,  1830. 


CONTENTS. 


PAGE. 

Translator's  Preface  v 

Preface xii 

Memoir  on  the  life  and  writings  of  Beclard  1 

Introduction 19 

SECTION  I.  Of  organized  bodies ib. 

Of  animals  26 

Of  vertebrate  animals 58 

Of  the  viviparous  vertebrate  animals  -  70 

IL  Of  the  human  body 74 

Of  the  fluids 79 

Of  the  organs 84 

Ofthe  organism -  94 

Of  the  development  and  differences  of  the  organization  98 

Of  the  alterations  of  the  organization     -  104 

Of  death  and  the  cadaver         .....  106 

CHAPTER  I. 

Of  the  cellular  and  adipose  tissues 113 

SECTION  I.  Of  the  cellular  tissue  ib. 

II.  Ofthe  adipose  tissue      ...                 ...  128 

ART.  I.  Of  the  common  adipose  tissue       ...  129 

II.  Of  the  medullary,  or  adipose  tissue  of  the  bones  140 

CHAPTER  II. 

Of  the  serous  membranes  -        -        -        -        -        -        -147 

SECTION.  I.  Ofthe  serous  membranes  in  general  148 

II.  ART.  I.  Of  the  sub-cutaneous  synovial  bursx        -        -  160 

II.  Of  the  synovial  membranes  of  the  tendons    -  162 

III.  Of  the  articular  synovial  capsules     -         -  166 

IV.  Of  the  serous  splanchnic  membranes    -        -  173 


XIV  CONTENTS. 

PAQI. 
CHAPTER  III. 

Of  the  tegumentary  membranes 181 

SECTION  I.  Of  the  tegumentary  membranes  generally                   -  182 

II.  Of  the  mucous  membrane 191 

ffl.  Of  the  skin 204 

ABT.  I.  Of  the  skin  in  general 205 

H.  Of  the  appendages  of  the  skin       ...  226 

I.  Of  the  nails ib, 

H.  Of  the  hairs 230 

CHAPTER  IV. 

Of  the  vascular  system 237 

SECTION  I.  ART.  I.  Of  the  the  vessels  generally           ...  239 

II.  Of  the  termination  of  the  vessels        -        -        -  251 

I.  Of  the  capillary  vessels      ....  252 

II.  Of  the  erectile  tissue 269 

III.  Of  the  vascular  ganglia      ....  273 

H.  Of  the  arteries       -                         .....  275 

HI.  Of  the  veins 293 

IV.  Of  the  lymphatic  system 305 

ART.  I.  Of  the  lymphatic  vessels      ....  jj. 

II.  Of  the  lymphatic  ganglia                                   -  311 

CHAPTER  V. 

Of  the  glands          - 315 

CHAPTER  VI. 

Of  the  ligamentous  tissue 323 

SECTION  I.  Of  the  ligamentous  tissue  generally    -  324 

II.  Of  the  ligamentous  organs  in  particular           -        -        -  330 

ART.  I.  Of  the  ligaments ib. 

n.  Of  the  tendons          - 332 

HI.  Of  the  ligamentous  envelopes        -        -        -  334 

A.  Of  the  envelopes  of  the  muscles         -        -  ib. 

B.  Of  the  sheaths  of  the  tendons  336 

C.  Of  the  periosteum ib. 

D .  Of  the  fibrous  envelopes  of  the  nervous  system  338 

E.  Of  the  compound  fibrous  membranes  -        -  ib. 

F.  Of  the  fibrous  capsules  of  some  organs     >  339 
in.  Of  the  fibro-cartilaginous  tissue ib. 

CHAPTER  VII. 

Of  the  cartilages                                                                         -        -  344 


• 


CONTENTS.  XV 

PAGE. 

SECTION  I.  Of  the  cartilages  in  general 345 

II.  Of  the  different  kinds  of  cartilages                 -        -        -  349 

ART.  I.  Of  the  articular  cartilages      ....  i b. 

II.  Of  the  costal,  laryngeal  and  other  cartilages     -  352 

III.  Of  the  membraniform  cartilages    -  355 

CHAPTER  VIII. 

Of  the  osseous  system      -        -        - 356 

SECTION  I.  Of  the  bones 358 

II.  Of  the  articulations -  395 

III.  Of  the  skeleton-        -  405 

CHAPTER  IX. 

Of  the  muscular  system 409 

SECTION  I.  Of  the  muscular  system  generally 411 

II.  Of  the  interior  muscles 437 

III.  of  the  exterior  muscles 441 

CHAPTER  X. 

Of  the  nervous  system 457 

SECTION  I.  Of  the  nervous  system  generally  464 

H.  Of  the  nerves  in  general 485 

III.  Of  the  ganglions  and  sympathetic  nerve     -        -        -  502 

CHAPTER  XL 

Of  accidental  productions 519 

SECTION  I.  Of  accidental  humours ib. 

II.   Of  stony  concretions 523 

III.  Of  accidental  tissues 525 

ART.  I.  Of  analogous  accidental  tissues  527 

II.   Of  heterologous  accidental  tissues  ib. 

I.  Of  tubercles                                     -        -        -  528 

II.  Of  the  encephaloid  tumour  529 

III.  Ofschirrus        -  531 

IV.  Ofmelanosis                                                      -  532 
V.  Of  cirrhosis,  &c.  533 

VI.  Of  compound  morbid  tissues         ...  534 

IV.  Of  foreign  animated  bodies  535 
ART.  I.  Of  intestinal  worms  - ib. 

I.   Of  vesicular  worms   -----  536 

II.  Of  the  flat  worms                                            -  537 

III.  Of  cylindrical  worms         ....  538 
II.  Of  parasitic  animals  540 


PREFACE. 

The  work  I  publish  is  a  compendium  of  a  course  of  anatomy, 
which  I  have  been  delivering  for  these  ten  years  past ;  and 
is  solely  intended  for  students  of  medicine.  My  object  in 
publishing  it,  is  to  offer  them,  in  a  small  volume,  an  abridg- 
ment of  the  numberless  labours  undertaken  for  more  than 
twenty  centuries,  in  the  science  of  the  organization  of  man. 

I  divide  the  anatomy  of  man  into  general  anatomy,  special 
anatomy  of  the  organs,  and  anatomy  of  the  regions.  This 
volume  contains  only  the  General  Anatomy,  and  may  be  con- 
sidered either  as  a  separate  work,  or  as  the  first  part  of  a  ge- 
neral treatise. 

In  writing  this  part  of  Anatomy,  I  have  made  a  liberal  use 
of  the  work  of  our  celebrated  Bichat,  as  well  as  of  those  works 
which  have  since  been  published  on  the  same  subject.  I  have 
also  consulted  treatises  ex-professo,  for  each  system  or  kind 
of  organs.  I  have  been  careful  to  quote  in  every  chap- 
ter, the  titles  of  the  works  which  furnished  me  with  the  ma- 
terials necessary  to  compose  it,  less  with  the  view  of  making 
an  easy  and  vain  display  of  erudition,  than  to  exempt  others 
from  the  necessity  of  reading  the  works  which  1  was  myself 
obliged  to  peruse;  and  at  the  same  time  to  point  out,  to  those 
who  are  anxious  to  make  farther  researches  and  more  profound 
studies,  a  sort  of  select  anatomical  library.  I  have  also  indi- 
cated the  plates,  which  may  be  consulted  with  advantage  for 
each  kind  of  organ. 
2 


VI  PREFACE. 

1  have  begun  each  chapter,  with  an  abridged  history  of 
the  principal  discoveries  made  respecting  the  system  of  organs 
which  comj&ose  it;  to  enable  me,  the  better  to  compile  some 
of  these  historical  notices,  I  made  free  use  of  Lauth's  History 
of  Anatomy,  of  which  as  yet  one  volume  only  is  published. 

The  introduction  treats,  in  the  first  section,  of  organization 
in  general,  and  in  the  second,  of  the  human  body.  It  was  my 
intention,  in  the  first  section,  to  give  merely  to  my  reader  a 
general  idea  of  comparative  anatomy  and  physiology.  In  so 
doing,  it  was  not  my  object  to  exempt  the  student  from 
studying  the  anatomy  of  animals;  but  on  the  contrary,  to 
show  them  the  utility  of  this  kind  of  knowledge.  In  writing 
this  part  of  the  introduction,  I  have  profited  by  the  labours  of 
Dumeril,  Blainville,  Geoffroy  Saint  Hilaire,  Lamarck,  and 
especially  of  those  of  Cuvier,  whom  I  could  have  cited  at 
every  page.  In  the  second  part  of  the  introduction,  I  have 
given  general  views  of  the  human  body  ;  I  have  spoken  of  its 
humours  generally,  part  of  the  science  of  organization  too 
much  neglected,  since  Haller  and  his  school,  who  erroneously 
thought  they  had  found  the  whole  secret  of  life  in  the  nervous 
system,  and  in  the  phenomena  of  irritability  and  sensibility. 

Anatomy  not  being  an  object  of  mere  speculation  and  sterile 
curiosity  to  the  physician,  but  the  basis  of  all  knowledge  re- 
lating to  medicine,  I  thought  that  physiology  and  pathology, 
ought  not  to  be  entirely  separated  from  it.  Pathological 
anatomy,  particularly,  ought,  in  my  estimation,  to  be  connected 
with  special  anatomy,  and  in  this  view,  the  description  of  each 
tissue  is  terminated,  by  a  brief  survey  of  the  varieties  and 
alterations  therein  observed,  and  the  whole  work  itself  is  con- 
cluded by  a  chapter  on  anomalous  or  accidental  productions, 
common  to  all,  or  to  several  kinds  of  organs. 

P.  A.  BECLARD. 

Paris,  August  30th,  1223. 


ON   THE 


LIFE  AND  WRITINGS 


OF 


BECLARD. 


To  write  the  life  of  a  celebrated  man,  is  at  once  to  honour 
his  memory,  and  confer  a  benefit  on  society;  for,  while  we 
recall  to  mind  the  triumphs  of  him  whose  every  step  was 
crowned  with  success,  we  teach  those  who  wish  to  imitate  him, 
by  what  means  glory  is  attained,  and  of  what  value,  in  this 
world,  is  a  reputation  justly  acquired.  It  is  with  this  double 
object  in  view,  that  we  propose  to  lay  before  our  readers,  the 
laborious  life  of  the  learned  man,  whom  the  school  of  medicine 
of  Paris  will  long  regret,  and  of  which  he  was  one  of  the  no- 
blest ornaments. 

Peter  Augustine  Beclard  was  born  at  Angers,  October  12th, 
1785.  His  parents  had  no  other  fortune  than  their  good  name, 
and  in  their  family  probity  was  hereditary.  His  father,  al- 
though loaded  with  the  cares  of  a  numerous  family,  by  a  strict 
economy,  was  enabled  to  give  to  each  of  his  children  the  ele- 
mentary education,  requisite  to  enable  them  to  continue  the 
limited  business  which  supported  them.  Thus,  when  young 
Beclard  had  learned  to  read,  write  and  cipher,  he  was  made  to 
understand  that  to  this,  the  extent  of  his  knowledge  should  be 
confined.  But  either  because  he  had  a  foreboding  of  his  future 
success,  or  that  he  was  inspired  by  instinct,  or  by  an  irresisti- 
ble inclination,  Beclard,  heedless  of  these  remarks,  eagerly 
read  every  book  which  fell  into  his  hands. 


2  LIFE  AND    WRITINGS   OP    BECLARD. 

The  central  schools,  which  had  been  established  in  the  de- 
partments, and  from  the  heart  of  which  radiated  the  instruc- 
tion destined  to  enlighten  a  regenerated  nation,  were  then  in 
all  their  activity.  Beclard  had  himself  inscribed  as  one  of  the 
pupils  of  that  formed  at  Angers,  and  he  was  soon  remarked 
for  his  proficiency  and  rapid  improvement.  Here,  for  the  first 
time,  he  discovered  the  advantages  of  study;  here  he  was  im- 
bued with  the  love  of  the  sciences,  and  here  he  learned  to 
worship  them.  Notwithstanding  the  illusions  with  which  he 
already  fed  his  ardent  soul,  his  relations  saw  with  sorrow  such 
dispositions  developed  in  him,  and  in  order  to  keep  him  in 
the  rank  in  which  he  was  born,  they  from  time  to  time,  tried 
to  make  of  him  a  clerk  of  a  store,  then  of  a  lottery  office,  and 
at  last  secretary  to  the  director  of  the  stage-office.  Beclard 
but  ill  fulfilled  those  employments  for  which  he  had  great  re- 
pugnance, and  but  little  aptitude;  and  indeed,  he  was  consi- 
dered by  his  employers  as  unfit  for  the  occupations  of  busi- 
ness. The  disgust  that  he  experienced  in  this  situation,  very 
unsuitable  to  his  natural  inclinations,  from  this  moment  tinged 
with  melancholy  the  character  of  Beclard,  which  afterwards 
redounded  to  his  advantage,  by  early  preparing  his  mind  for 
that  kind  of  meditation  which  the  profound  cultivation  of 
science  always  demands. 

There  is  an  epoch  in  the  life  of  man,  when  as  yet  undecided 
on  the  profession  he  shall  embrace,  he  studies,  as  it  were,  the 
part  he  is  to  perform  on  the  theatre  of  the  world,  and  prepares 
himself  beforehand  to  fulfil  it  well.  This  period  in  the  life  of 
Beclard,  was  marked  with  such  indolence,  as  reduced  his 
family  to  despair;  he  is  fit  for  nothing,  said  they,  and  neglect- 
ful of  the  future: — this  was  owing  to  their  having  misunder- 
stood his  secret  intentions,  and  to  the  want  of  the  aliment  they 
required;  but  as  soon  as  his  father  was  enlightened  by  good 
advice,  softened  by  the  solicitations  of  his  son,  who  only  wish- 
ed to  become  a  surgeon  in  the  army,  and  had  permitted  him 
to  follow  the  medical  courses  established  in  the  hospital  of  the 
same  city,  from  that  moment  did  the  young  student  see  open- 
ed before  him  a  profession  in  which  he  ardently  desired  to 


LIFE    AND    WRITINGS    OF    BECLARD. 

enter,  from  that  moment  also  ceased  that  torpor  which  had  so 
long  held  his  faculties  in  chains. 

He  began  the  study  of  medicine  in  1S14.  A  circumstance 
soon  presented  itself,  as  if  on  purpose,  to  give  to  Beclard  a 
knowledge  of  his  powers:  a  competition  occurred  for  the  first 
time  for  the  situation  of  resident  physician  in  the  hospital. 
One  of  the  pupils,  who  since  has  been  lost  in  the  crowd,  had 
then  a  reputation,  we  might  say  brilliant,  for  every  age  has  its 
kind  of  celebrity,  and  was  considered  as  a  very  formidable 
competitor;  so  much  so  as  to  fix  the  eyes  of  every  one  on 
him,  for  that  situation.  Notwithstanding  this,  Beclard  so  as- 
tonished his  judges  with  the  extent  of  his  knowledge,  and  the 
precision  of  his  language,  that  he  was  proclaimed  the  success- 
ful candidate.  This  was  the  first  glimpse  of  that  glory  which 
was  to  shine  on  him,  even  to  his  tomb. 

During  his  residence  in  the  hospital  of  Angers,  he  conse- 
crated almost  all  his  time  to  the  study  of  anatomy — -a  study  for 
which  he  had  a  great  predilection;  he  accustomed  himself  to 
observe  every  kind  of  malady,  which  were  infinitely  varied, 
and  which  presented  themselves  in  an  abode  opened  to  all  the 
miseries  to  which  humanity  is  subject.  He  habituated  himself 
to  a  skilful  manipulation  of  the  knife.  He  studied  with  expert 
masters,  among  whom  Mirault  was  a  distinguished  practi- 
tioner, and  whose  name  is  enrolled  in  the  pages  of  our  art.  He 
learned,  I  say,  to  interpret  with  wisdom,  and  without  preju- 
dice, the  facts  which  abound  in  our  science,  and  from  which 
we  are  often  exposed  to  draw  conclusions  favourable  to  our  fa- 
vourite opinions;  finally,  he  received  from  this  school,  more 
useful  than  celebrated,  the  germ  of  a  correct  knowledge,  and 
of  that  eclectic  and  rigorously  exact  mind  which  afterwards 
rendered  him  so  valuable  a  man.  The  example  of  Beclard, 
and  his  success,  prove,  better  than  a  long  argument,  the  utility 
of  elementary  or  secondary  schools  of  medicine,  where  the 
number  of  pupils  being  small,  they  have  a  better  opportunity 
to  observe  for  themselves,  and  consequently,  are  enabled  early 
to  obtain  that  experience  which  in  the  larger  schools,  the  eager 
crowd  of  students  never  acquire  but  with  the  greatest  trouble. 
Thus  we  see  him  leaving  the  retired  scenes  of  his  first  studies, 


4  LIFE    AND    WRITINGS    OF    BECLARD. 

already  rich  in.  scientific  lore,  if  not  very  extensive,  at  least 
very  positive. 

During  the  first  years  of  his  medical  studies,  he  devoted 
himself  to  the  study  of  the  Latin  language  and  philosophy, 
which  the  clergyman  attached  to  the  hospital  taught  him,  and 
who  delighted  to  instruct  a  young  man  already  so  rich  in 
knowledge.  He  cultivated  at  the  same  time  Botany;  he  ob- 
tained several  premiums  on  subjects  of  natural  history,  and  by 
his  zeal,  ardour,  and  success,  from  this  time,  gave  hopes  of  a 
brilliant  career.  Beclard,  during  his  residence  in  the  hospital 
of  Angers,  left  to  his  successors  a  noble  example  of  emulation 
which  will  be  long  remembered. 

At  this  time  Bichat  had  reached  the  middle  course  of  his 
career,  and  filled  the  learned  world  with  his  glory  and  his 
name.  In  the  many  conversations  young  Beclard  had  with 
his  relations,  he  often  remarked  how  happy  he  should  be  if  he 
were  one  day  able  to  cope  with  the  Father  of  General  Anato- 
my and  become  his  equal.  Bichat  was  his  idol;  he  was  anxious 
to  render  homage  to  his  genius  and  be  considered  one  of  his 
followers.  Unfortunately  for  Beclard,  Bichat  died  before  he 
was  able  to  attend  his  lectures,  for  it  was  not  until  1808,  that 
he  went  to  Paris;  but  he  had  carefully  transcribed  notes  taken 
at  the  last  course  of  this  celebrated  anatomist.* 

In  1808,  Beclard  was  distinguished  in  the  first  rank  of  the 
pupils  of  the  Practical  School  or  clinical  courses,  and  of  the 
hospital  of  Paris.  In  1809,  premiums  were  conferred  on  him 
by  the  medical  school,  on  subjects  of  anatomy,  physiology, 
medical  natural  history,  chemistry,  and  physicks.  He  was 
soon  after  appointed  resident  physician  (eleve  interne,)  to  va- 
rious hospitals.  He  again,  1810,  received  premiums  on  anato- 
my, physiology,  medicine  and  surgery;  and  Mr.  Roux  select- 
ed him  for  the  honourable  office  of  preparing  and  repeating 
lectures  at  the  hospital  of  La  Charite. 

Hitherto,  Beclard  was  only  known  to  his  rivals  in  fame, 
and  to  his  friends;  and  all  his  merit  only  consisted  in  a  vast 

*  This  passage  alludes  particularly  to  the  work  of  Bichat  on  Pathological 
Anatomy,  which  was  published  from  an  authographic  MS.  of  Bdclard,  and 
which  are  the  only  authentic  notes  we  possess  of  Bichat's  last  course. 

TRANS. 


LIFE  AND  WRITINGS  OP  BECLARD. 

memory  and  an  easy  elocution.  His  genius  had  not  yet  as- 
sumed a  determinate  character;  as  yet,  no  original  production 
had  unveiled  his  resources;  but  at  last  an  important  occasion 
of  distinguishing  himself  occurred.  M.  Dupuytren  being  ap- 
pointed to  the  chair  of  operative  surgery,  the  place  of  adjunct 
professor  of  anatomy  in  the  faculty  of  Paris  became  vacant. 
Beclard,  being  appointed  assistant,  in  1811,  he  presented  him- 
self as  a  candidate,  and  to  him  was  awarded  the  prize  by  the 
judges.  He  had  already  acquired  the  esteem  of  a  great  many 
students  who  had  followed  his  private  courses.  He  had  scarce- 
ly any  reputation  as  an  anatomist;  but  as  soon  as  he  saw  that 
he  was  surrounded  with  so  many  means  of  instruction,  he  has- 
tened to  improve  himself  by  taking  advantage  of  the  opportu- 
nity presented  to  him.  Besides,  he  Had  already  indicated  in 
the  thesis  that  he  presented  for  the  abovte  mentioned  situation, 
in  the  most  luminous  manner,  what  ouglt  to  be  the  conduct 
of  the  superintending  adjunct  towards  tlfe  pupils  in  the  pur- 
suit of  anatomical  knowledge.  It  was  therefore  expected,  that 
faithful  to  the  principles  that  he  himself  had  laid  down,  he  would 
not  fail  to  put  them  in  practice;  and  it  is  well  known  that  he 
did  not  belie  the  hopes,  that^his  zeal  and  precocious  talents  had 
led  the  profession  to  expect. 

Among  the  interesting  facts  collected  by  him,  in  the  dissect- 
ing rooms  of  the  medical  school,  and  which  he  presented  to 
the  society  of  the  professors,  among  whom  he  was  very  soon 
received,  we  will  only  mention  the  principal  ones.  Such  was 
the  observation  of  a  foetus  born  with  a  frontal  and  very  volu- 
minous hernia  of  the  brain,  being  the  consequence  of  hydro- 
cephalus.  This  preparation  was  rendered  particularly  curious 
by  the  extraordinary  existence  of  two  bones  situated  between 
the  frontal  bones  and  not  far  from  their  articulation  with  the 
ossa  nasi. 

Soon  after,  he  gave  the  description  of  a  foetus,  of  which  the 
umbilical  cord  very  much  dilated  at  its  base,  contained  a  part 
of  the  abdominal  organs,  and  the  heart  of  which  adhered  to 
the  palate.  He  published,  conjointly  with  JVK  Bonnie,  a  case 
of  labour  per  ano,  of  a  child  the  conception  of  Which  was  ex- 
tra-uterine. In  a  memoir  on  necrosis,  he  maintained  and  de- 


6  LIFE  AND  WRITINGS  OF  BECLARD. 

veloped  the  opinion  of  some  authors  who  think  there  is  in 
reality  no  regeneration  of  bone.  He  also  made  public  his  re- 
flections on  the  formation  of  the  callus;  he  demonstrated  to- 
gether with  Bonn  and  Bichat  that  the  ossification  of  the  perios- 
teum was  only  momentary,  and  served  as  a  sheath  to  the  two 
fractured  extremities  during  the  time  they  are  cemented  with 
phosphate  of  lime.  It  had  been  supposed  for  a  long  time,  that 
the  curvature  of  the  aorta  produced  the  lateral  curvature  of  the 
dorsal  region  of  the  vertebral  column.  Bichat  had  already 
shaken  the  general  belief  of  this  supposition,  by  supposing  that 
it  might  be  caused  by  the  often  repeated  contractions  of  the 
muscles  of  the  right  arm;  this  however  was  only  a  supposition, 
but  Beclard  demonstrated  it  to  be  a  positive  fact  by  numerous 
researches  upon  this  subject.  We  must  not  omit  to  mention, 
the  physiological  experiments  he  performed  in  order  to  prove 
that  the  foetus  has  respiratory  movements  while  in  the  uterus, 
by  which  it  introduces  the  waters  of  the  amnion  into  the  bron- 
chiae.  He  was,  however,  unable  to  demonstrate  that  this  liquid 
has  a  chemical  action  on  the  blood  which  enters  the  lungs.  It 
was  also  at  this  time  that  he  made,  with  the  assistance  of  Le 
Gallois,  a  series  of  curious  experiments  calculated  to  determine 
the  action  of  the  oesophagus  in  vomiting. 

In  1813,  B6clard  defended  before  the  faculty  of  Paris  his 
thesis  for  the  degree  of  Doctor  of  Medicine;  it  contains  seve- 
ral propositions,  which  treat:  1st,  of  the  distinction  to  be  esta- 
blished between  the  lamellated  and  adipose  tissues;  2d,  of  the 
projection  and  depression  of  bones,  which  he  conceives  to  be 
induced  by  the  primitive  formation  of  the  cellular  web  of  the 
bone,  and  not  to  the  traction  of  the  tendinous  attachment  of  the 
muscles.  Some  of  his  labours  already  cited,  are  again  pre- 
sented in  this  Thesis,  which  concludes  with  a  learned  inter- 
pretation and  with  practical  observations  on  the  method  of  per- 
forming the  lateral  operation  proposed  by  Celsus.  His  talents 
as  a  surgeon  had  been  already  justly  appreciated;  and  in  1814, 
at  the  time  of  the  first  invasion  of  France  by  the  allies,  he  was 
appointed  by  government  to  give  his  professional  aid  to  the 
wounded  soldiers  brought  to  the  ambulance,  established  at  the 
Hospital  Saint-Louis.  His  Memoir  on  Acephalus  appeared  in 


LIFE    AND    WRITINGS   OF    BECLARD.  7 

1815.  He  also  communicated  at  this  time,  several  facts  of 
pathological  anatomy,  that  he  had  observed  in  the  dissecting 
rooms  of  the  Practical  School. 

A  competition  then  arose  for  the  place  of  second  surgeon 
of  the  Hotel-Dieu,  and  Beclard,  for  the  first  time,  was  unsuc- 
cessful in  this  kind  of  contention:  Mr.  Marjolin  was  his  op- 
ponent. As  the  two  Candida* e.«,  however,  had  contended  for 
the  victory,  with  equal  merit  and  talents,  Beclard  was  appoint- 
ed surgeon  to  the  Hospital  of  La  Pitie.  He  had  already  ac- 
quired a  considerable  skill  in  the  art  of  Part  and  of  T.  L.  Petit, 
under  a  master  who  loved  him  tenderly,  and  with  whom 
he  was  afterwards  united  by  the  most  affectionate  ties  of  friend- 
ship. Dubois  had  taught  him  operative  surgery,  at  the  school 
of  Perfectionnement)  and  it  is  not  astonishing,  that  Beclard 
should  have  soon  developed  a  talent  truly  surgical,  to  which, 
however,  his  natural  dexterity,  and  his  daily  habit  of  dissec- 
tion, had  already  predisposed  him. 

In  1816,  he  became  a  member  of  the  Philomatic  Society, 
and  he  gave,  for  the  first  time,  a  course  on  General  Anatomy. 
In  1817,  appeared  his  researches  on  the  wounds  of  arteries. 
The  experiments  of  Jones,  in  England,  were  scarcely  known, 
when  our  anatomist  thought  it  proper  to  give  them  a  trial,  and 
the  result  of  his  labours  confirmed  the  conclusions  drawn  by 
the  English  experimenter.  This  memoir  is  to  be  found  among 
those  of  the  Soci&te  d* Emulation,  of  which  he  was  a  mem- 
ber. In  1818,  he  published  with  Mr.  J.  Cloquet,  a  transla- 
tion of  Lawrence's  treatise  on  hernia. 

It  was  also  during  the  same  year,  that  the  faculty  of  medi- 
cine, of  Paris,  received  him  as  one  of  its  members.  This 
memorable  event  in  the  life  of  Beclard,  in  adding  new  lustre 
to  his  reputation,  inspired  him  with  the  noble  ambition  of 
rendering  himself  equal  in  talent  to  the  celebrated  professors 
of  that  faculty,  old  in  glory  and  experience.  Thus,  did  we 
see  him  redouble  his  efforts,  in  order  to  fulfil  with  dignity  and 
talent,  the  chair  which  had  been  entrusted  to  him.  The  eager- 
ness with  which  the  students  attended  his  learned  courses  on 
Anatomy,  was  the  best  pledge  of  the  propriety  of  the  selec- 
tion the  faculty  had  made,  of  this  remarkable  man. 


8  LIFE    AND    WRITINGS  OF    BECLARD. 

He  aided  in  the  formation  of  a  scientific  selection  then 
known  under  the  name  of  the  Nouveau  Journal  de  Medecine, 
of  which,  Les  archives,  generales  de  Medecine,  are  now  a  con- 
tinuation. In  1819,  he  published  four  memoirs  on  Osteosis,* 
of  which  disease,  he  described  the  progress  with  the  greatest 
precision  and  perspicuity.  He  cooperated  in  the  publication 
of  the  Dictionary  of  technical  terms  of  Medicine,  Surgery, 
Pharmacy,  &c.  and  was  one  of  the  principal  colaborators  of 
the  Nouveau  Dictionnaire  de  Medecine. 

In  1820,  he  was  appointed  president  of  the  board  of  Juries 
of  the  department,  and  member  of  the  council  of  health  of 
the  department  of  the  Seine.  When  a  royal  ordinance  had 
created  the  Academy  of  Medicine,  (December  20th,  1820,) 
public  opinion  pointed  out  Beclard,  and  he  was  unanimously 
elected  to  fulfil  the  functions  of  secretary  for  life  of  that  learned 
body,  functions  that  he  exercised,  until  ministerial  favour  dis- 
posed of  his  office  otherwise. 

In  1821,  he  published  a  volume  of  additions  to  the  general 
Anatomy  of  Bichat,  and  the  following  year  gave  to  Mr.  Des- 
cot,  the  result  of  his  experience  and  researches  on  the  local 
affections  of  the  nerves,  which  the  latter  recorded  in  his  the- 
sis. In  1823,  he  published  his  Elements  of  General  Anato- 
my, whence  students  may  long  draw  the  most  impor- 
tant lessons  which  have  hitherto  been  given  on  the  organi- 
zation of  the  human  body. — At  this  time  Beclard  was  in- 
cluded in  the  general  disgrace  of  the  old  faculty  of  medicine, 
and  when  the  reorganization  of  the  new  school  was  about  to 
take  place,  he  came  very  near  being  excluded,  but  his  great 
reputation  and  his  talents  got  the  better  of  every  kind  of  in- 
trigue and  opposition  which  arose  against  him,  and  the  chair 
on  which  he  had  shed  a  new  lustre,  was  restored  to  him. 

This  rapid  recapitulation  of  the  labours  most  remarkable  in 
the  life  of  Beclard,  brings  us  to  a  gloomy  epoch  ;  but  before 
entering  on  this  painful  part  of  the  task  we  have  prescribed  to 
ourselves,  let  us  return  to  the  particulars  of  the  life  of  a  master 
so  dear  to  us  and  one  -who  honoured  us,  with  so  benevolent 

*  Beclard  has  given  this  name  to  the  branch  of  anatomy  which  treats  of 
the  developement  of  bone. 


LIFE    AND   WRITINGS    OF   BECLARD.  9 

a  friendship.    Let  us  therefore  consider  Beclard,  as  an  anato- 
mist, as  a  surgeon,  as  a  professor,  and  as  a  private  man. 

Anatomy  had  been  the  first  object  of  the  studies  of  Beclard. 
His  retentive  memory  enabled  him  to  recollect  most  faithfully 
the  minutest  descriptions ;  his  skill  enabled  him  to  perform 
the  most  difficult  dissections;  and  his  great  judgment  placed 
him  far  above  a  great  number  of  pupils,  whose  whole  ability 
consists  in  discovering  a  muscle,  or  in  following  up  the  mi- 
nute ramifications  of  an  artery.  Endowed  with  the  three- 
fold gift  of  dissecting  well,  of  seeing  well,  and  of  remember- 
ing exactly  the  relations  and  disposition  of  parts,  he  had 
in  himself,  all  the  requisite  qualifications  to  make  a  good  ana- 
tomist. When  he  arrived  in  Paris,  anatomy  and  physiology, 
already  greatly  improved  by  the  researches  and  labours  of 
Haller,  Bordeu,  and  Bichat,  beautifully  adorned  with  all  the 
brilliancy  of  their  genius,  powerfully  enticed  a  great  many 
students,  both  by  the  attraction  of  the  new  discoveries,  and 
with  the  hope  of  the  many  useful  applications  they  would  be 
able  to  make  of  them,  in  the  practice  of  medicine  and  surgery; 
consequently,  this  science  was  cultivated  with  an  indefatigable 
ardor,  which  was  kept  up  and  increased  by  the  example  and 
encouragement  of  such  men  as  Portal,  Chaussier,  and  Dum6- 
ril.  At  this  time  Pinel  had  already  established  important  dis- 
tinctions in  the  curative  art  founded  on  Anatomy  ;  and  the 
school,  of  which  he  was  the  leader,  followed  with  enthusiasm 
the  impulse  given  by  this  philosophical  physician.  It  was  at 
this  time  also,  that  the  indispensable  and  inseparable  know- 
ledge of  the  organization,  and  that  of  maladies  were  intimately 
united;  and  in  order  to  render  it  still  more  necessary,  while 
Messrs.  Richerand  and  Dupuytren  were  instructing  the  me- 
dical profession  with  the  healthy  action  of  our  organs,  Messrs. 
Bayle  and  Laennec  were  pointing  out  the  different  modes  of 
alterations  they  were  susceptible  of  experiencing. 

It  was  very  natural  that  Beclard  should  eagerly  embrace 
the  prevailing  opinions  of  his  age,  the  more  so  because  he 
was  capable  of  foreseeing  all  the  good  that  the  science  might 
derive  from  it.  He  never  confined  himself  therefore  to  the 
dry  and  sterile  study  of  descriptive  anatomy;  he  always  con- 


10  LIFE    AND    WRITINGS    OF    BECLARD. 

sidered  it  in  its  relations  with  Medicine  and  Surgery.  He 
consecrated  the  whole  of  his  time  to  the  study  of  the  relations 
of  the  parts  with  each  other,  to  the  varieties  of  forms  and  di- 
rections that  circumstances  may  cause  them  to  experience; 
and  not  being  able  to  find,  in  the  immense  number  of  facts 
which  he  daily  observed,  means  sufficiently  vast  to  multiply 
his  learning,  he  was  seen  thirsting  for  more  knowledge,  to 
extend  beyond  conception  the  limits  of  his  erudition.  Full 
of  admiration  for  the  German  school  of  medicine,  to  which 
we  owe  so  many  valuable  discoveries  in  the  science  of  orga- 
nization, he  early  familiarized  himself  with  the  labours  of 
Meckel,  Oken,  Tiedemann,  &c. — He  also  profited  by  the  dis- 
coveries of  the  celebrated  men  of  Great  Britain  and  Italy ; 
and  it  was  not  until  he  was  possessor  of  an  immense  mass  of 
facts  gathered,  so  to  say,  from  every  quarter  of  the  civilized 
world,  that  he  minutely  and  carefully  scrutinized,  aided  by 
his  vast  experience,  every  fact,  every  opinion,  and  every 
theory. 

Some  men,  envious  of  his  glory,  accused  him  of  being  a 
mere  compiler,  a  man  of  erudition,  but  denied  that  he  pos- 
sessed even  the  smallest  particle  of  genius.  Let  us  not  forget, 
therefore,  that  in  following  this  course,  and  in  fulfilling  so 
difficult  a  task,  Beclard  needed  to  possess  a  correct  and  rapid 
intellect,  an  uncommon  eclectic  mind,  and  a  very  superior 
power  of  reasoning.  The  parallel  that  some  persons  have 
tried  to  establish,  between  Bichat  and  Beclard,  can  not  really 
exist.  If  these  two  men  have  between  them  some  resem- 
blance as  to  their  early  and  rapidly  acquired  glory,  and  unex- 
pected and  premature  end,  they  essentially  differ  as  to  the 
manner  in  which  they  cultivated  that  science  they  have 
equally  improved.  Rich  with  his  own  native  genius,  carried 
along  by  the  desire  of  constructing  the  medical  edifice  on  a 
new  plan,  Bichat  hastened  to  arrange  the  materials  for 
which  he  was  almost  entirely  indebted  to  his  own  researches. 
B6clard,  on  the  contrary,  formed  in  his  mind  the  vast  project 
of  collecting  all  the  scattered  facts  belonging  to  the  science, 
in  order  to  create  with  them  a  code  of  doctrines  authorized 
by  the  most  celebrated  names,  and  supported  by  the  result  of 


LIFE    AND   WRITINGS   OP   BECLARD.  11 

the  meditations  of  the  most  learned  men.  B6clard  preferred 
the  merit  of  making  truth  shine,  it  mattered  not  from  what 
quarter  it  proceeded,  to  the  dazzling  glory  of  being  an  inven- 
tor. He  was  unaffectedly  the  greatest  admirer  of  Bichat,  and 
if  he  has  often  been  obliged  to  controvert  his  opinions,  it  was 
because  the  interest  and  the  advancement  of  the  science  de- 
manded it. 

The  same  distinction  which  has  been  made  between  Bos- 
suet  and  Massillon,  might  be  established  between  Bichat  and 
Beclard.  The  Bishop  of  Meaux  was  one  day  preaching 
to  an  illustrious  auditory  ;  Massillon,  who  was  listening  to 
him,  said,  "  This  is  very  well,  I  admire  him ;  but,  if  I  were 
in  his  place,  I  should  preach  otherwise."  Such  was  the  con- 
duct of  Beclard  with  respect  to  Bichat.  Cooler  and  less  en- 
thusiastic, he  came  after  him,  as  it  were,  to  correct  the  errors 
which  had  passed  unnoticed  by  the  inventive  genius  of  that 
great  man.  Let  us  therefore  cease  to  establish  between  them 
a  comparison  which  does  not  permit  us  to  judge  of  either,  ac- 
cording to  his  respective  merit.  They  are  only  to  be  consid- 
ered singly,  and  then  their  individual  merit  will  cause  us  to 
admire  them  the  more. 

It  is  in  consequence  of  this  plan  of  reform  and  improve- 
ment, that  Beclard  first  published  a  new  edition  of  Bichat's 
General  Anatomy,  with  a  volume  of  additions,  and  in  the 
same  spirit  of  improvement,  he  afterwards  brought  to  light 
his  Elements  of  General  Anatomy,  a  work  remarkable  for 
its  clearness,  the  great  number  of  truths  it  contains,  the  ex- 
tensive plan  on  which  it  was  written,  and  the  immense  erudi- 
tion therein  displayed.  This  work  has  been  compared  to  the 
Manual  of  General,  Descriptive  and  Pathological  Anatomy  of 
Meckel.  It  is  very  true  that  the  French  anatomist  has  been 
sometimes  benefited  by  this  great  collection  of  facts  more  or 
less  interesting  ;  but  how  much  the  imitator  has  surpassed  his 
original ;  with  what  art  he  has  avoided  those  German  ideas, 
those  hypothetical  explanations,  and  those  often  far  fetched 
analogies  with  which  the  General  Anatomy  of  Meckel  is  in- 
terspersed. On  the  other  hand,  the  work  of  Beclard  is  com- 
pared to  that  of  Bichat,  the  enchanting  style  of  which  is  con- 


13  LIFE    AND   WRITINGS   OF   BECLARD. 

tinually  praised  ;  but  we  must  not  forget  that  Bichat  wrote  at 
a  time  when  it  was  necessary  to  entice  the  reader  by  the  charm 
of  diction,  while  Beclard  wrote  for  sober  men,  whom  science 
alone  can  seduce,  without  the  artifice  of  meretriciousornaments. 
Beclard  carries  in  himself  the  distinctive  marks  of  his  age. 
Bichat  has  written,  as  is  said,  the  romance  of  the  science,  but 
Beclard  has  striven  to  fix  its  laws,  and  to  draw  up  its  code. 
Thus,  the  General  Anatomy  of  Beclard  possesses  its  peculiar 
merit,  and  may  be  considered  as  one  of  the  most  glorious 
titles  of  the  author  to  immortality.  To  conclude,  this  learned 
man  has  especially  studied  and  improved  anatomy,  in  its  re- 
lations with  medicine  and  surgery,  and  by  strengthening  the 
foundation  of  this  science  with  an  unlimited  erudition,  has 
really  founded  a  school,  the  principles  of  which  will  be  long 
followed. 

To  the  valuable  qualities  that  we  have  just  enumerated,  Be- 
clard added  those  of  a  skilful  operator.  He  was  endowed 
with  a  steady  presence  of  mind,  with  a  firmness  which 
never  approached  harshness,  and  with  a  dexterity  which  was 
the  result  of  his  many  dissections.  Unforeseen  circumstan- 
ces sometimes  obliges  the  operator  to  deviate  from  the  general 
rules  of  the  art.  Beclard,  on  these  occasions,  knew  how  to 
modify  a  method,  or  invent  a  new  one  to  suit  the  case.  His 
composure  never  abandoning  him,  his  memory  recalled,  or  his 
genius  often  suggested  to  him,  during  an  operation,  every 
thing  requisite  to  insure  its  success.  He  has  invented  or  im- 
proved the  methods  of  several  operations:  such  are  his  method 
for  curing  the  fistula  of  the  duct  of  steno  ;  several  methods 
for  the  partial  amputation  of  the  foot,  the  amputation  of  the 
articulation  of  the  metatarsus,  the  amputation  of  the  articulation 
of  the  shoulder  and  hip  joint.  He  has  also  modified  the  man- 
ner of  cutting  through  the  soft  parts  in  amputating  limbs, 
and  the  method  of  sawing  the  tibia  in  the  amputation  of  the 
leg.  He  was  the  first  who  removed  the  parotid  gland;*  finally 

*  It  is  strange  we  should  so  often  read  of  European  surgeons  extracting 
this  gland,  while  in  this  country  some  of  the  greatest  authority  in  surgery 
deny  the  possibility  of  the  operation.  On  the  one  hand,  we  can  not  sup- 
pose that  these  surgeons  wish  to  impose  on  us,  and  on  the  other,  to  say 


LIFE    AND   WRITINGS   OP   BECLARD.  13 

he  modified  to  great  advantage   the  method  of  Celsus  in  the 
lateral  operation. 

His  vast  erudition  was  equally  extensive  in  surgery.  In 
his  lectures,  delivered  at  the  Hospital  of  La  Piti6,  he  gave 
unquestionable  proofs  of  an  extensive  and  solid  knowledge. 
Even  those  who  confined  themselves  to  his  course  of  lectures 
on  surgery,  and  who  disdained  to  attend  his  operations,  ex- 
hibited on  a  very  modest  theatre,  could  not,  at  least,  deny  him 
the  merit  of  being  extremely  well  versed  in  Surgical  litera- 
ture. He  was  always  the  general  admiration  of  his  audience, 
in  seeing  with  what  extraordinary  talent  he  developed  and 
commented  on  the  theories  of  those  men  who  have  written  on 
this  branch  of  the  healing  art.  It  is  useless  to  endeavour  to 
avenge  here  Beclard  for  the  character  with  which  he  was  re- 
proached, of  being  a  surgeon  only  in  theory.  Let  us  not 
mingle  with  the  pleasure  we  experience  in  recording  the  merit 
and  talents  of  this  excellent  man,  the  bitter  remembrance  of 
the  numerous  persecutions  and  ridiculous  cabals,  of  which  he 
was  the  object.  The  reputation  of  Beclard,  as  a  professor, 
was  spreading  more  and  more  every  day.  He  possessed  the 
very  rare  faculty  of  presenting  methodically,  with  precision 
and  simplicity,  all  that  his  extraordinary  memory  had  retain- 
ed. He  was  particularly  happy  in  the  selection  of  his  words 
and  in  the  construction  of  his  phrases.  He  preferred  preci- 
sion and  vivacity  of  expression  to  elegance.  His  language 
was  parsimonious  of  metaphors  ;  but  he  developed  his  ideas 
by  a  gradation  of  words  admirably  chosen,  so  that  the  last  ex- 

that  such  great  anatomists  as  Beclard,  and  a  great  many  other  European 
surgeons,  such  as  Speranza,  Lisfranc  and  others  who  published,  having  re- 
moved the  parotid,  have  been  mistaken,  and  that  they  have  only  extracted 
an  enlarged  lymphatic  gland,  is  more  than  we  are  disposed  to  assert.  That 
this  may  have  been  sometimes  the  case,  I  entertain  no  doubt,  for  three  years 
ago,  Dr.  Gibson  performed  an  operation  which,  as  he  correctly  observed, 
might  have  been  palmed  on  a  class  of  students,  as  being  an  operation  for  the 
removal  of  the  parotid,  whilst  it  was  only  an  enlarged  lymphatic  r  nd.  But 
at  the  same  time,  if  any  reliance  is  to  be  placed  on  the  word  01  aJeclard,  I 
think  we  can  not  deny  him  the  glory  of  having  performed  this  difficult 
operation.  TBASS. 


14  LIFE    AND   WRITINGS    OF   BECLARD. 

pression  being  the  most  impressive  and  the  most  energetic, 
left  in  the  mind  of  his  audience  the  image  of  the  object,  or 
the  idea  deeply  impressed.  He  slowly  prepared,  and  for  a 
longtime  matured  his  lessons  ;  being  perfectly  master  of  the 
subject  on  which  he  was  about  to  lecture,  he  never  was  in  the 
least  embarrassed  before  his  pupils.  He  always  united  there- 
suit  of  his  own  meditations,  to  the  knowledge  he  had  acquired: 
he  interested  and  captivated  his  hearers  without  having  re- 
course to  a  vain  show  of  language,  by  which  the  deceived 
multitude  is  sometimes  seduced. 

In  his  last  course  he  gave  an  anatomical  and  physiological 
history  of  the  nervous  system  ;  a  delicate  and  truly  difficult 
subject.  Nevertheless,  his  descriptions  were  so  very  clear 
and  there  was  in  them  so  much  order,  that  it  was  impossible 
not  to  understand  his  lectures.  He  has  presented  with  the 
greatest  perspicuity  the  endless  opinions  advanced  on  this 
subject  from  Praxagoras  down  to  this  present  time.  His  lec- 
tures were  now  more  attractive  and  more  instructive  than 
ever,  and  as  if  presageful  of  his  approaching  end,  he  always 
lectured  more  than  the  time  allotted  to  him,  and  could  not 
withdraw  from  that  chair,  which  soon  a  funeral  mantle  was 
to  shade. 

If  Beclard  had  his  equals  in  some  branches  of  the  healing 
art,  as  a  lecturer  he  was  surpassed  by  none  ;  but  on  the  con- 
trary he  eclipsed  most  of  his  cotemporaries.  He  reminded 
us  of  the  knowledge  and  eloquence  of  Halle,  and  was  at  least 
equal  to  Cuvier,  whom,  however,  he  delighted  to  imitate,  and 
to  the  height  of  whose  reputation  he,  by  his  vast  know- 
ledge, was  every  day  attaining.  He  failed  only  in  one  respect, 
and  that  was,  his  not  being  able  to  draw,  and  in  so  doing  to 
render  even  more  striking  his  descriptions  ;  had  Beclard  pos- 
sessed this  talent,  he  would  have  been  the  most  astonishing 
professor,  that  the  medical  sciences  had  ever  had  as  their  in- 
terpreter, till  the  present  time. 

It  is  not  common  to  meet  with  the  virtues  which  adorn  a 
private  character  united  to  great  talents ;  because  ambition,  the 
ordinary  source  of  our  misdeeds,  often  accompanies  genius, 
and  by  wishing  to  gratify  that,  we  are  exposed  to  deviate 


LIFE    AND   WRITINGS   OF   BECLARD.  15 

from  the  rules  of  social  morality.  This  can  not  be  said  of 
Beclard.  If  he  desired  to  occupy  a  distinguished  rank  among 
his  fellow  men,  it  was  never  at  the  expense  of  those  who  fol- 
lowed the  same  career  as  himself,  that  he  attained  it.  His 
success  in  the  numerous  competitions  he  had  for  various  offi- 
ces, had  distinguished  him  from  the  multitude,  and  he  main- 
tained himself  in  the  elevated  rank  he  occupied,  by  his  person- 
al merit,  and  his  indefatigable  labours.  He  has  been" accused 
of  being  ambitious  ;  but  his  noble  emulation  was  ill  inter- 
preted ;  if  he  desired  to  become  rich,  it  was  the  better 
to  relieve  a  numerous  family,  of  which  he  was  the  glo- 
rious support.  Could  a  man  be  ambitious,  who  delivered 
public  lectures  for  more  than  two  thirds  of  every  day,  thus 
neglecting  to  seek  a  practice  that  his  great  reputation  could 
not  have  failed  to  procure  him?  Simple  and  modest  in  his  taste 
and  habits,  he  delighted  to  live  quietly  in  the  bosom  of  a  family 
that  several  kinds  of  talents  contributed  to  render  illustrious. 

Beclard  was  naturally  melancholy  and^gloomy.  His  health, 
exhausted  by  long  continued  studies,  demanded  the  greatest 
care.  Always  intensely  occupied  with  abstract  ideas,  his 
manner  at  first  was  cold,  and  his  conversation  very  laconic; 
but  if  by  any  means  he  was  enticed  away  from  his  favourite 
meditations,  then  his  mind  was  perceived  to  be  ornamented 
with  the  lore  of  philosophy  and  history,  and  to  possess"  all 
those  charms  which  a  man  remarkable  for  the  brilliancy  and 
variety  of  knowledge  can  infuse  into  his  conversation.  His  hi- 
larity and  cheerfulness  appeared  only  at  intervals  and  quickly 
vanished;  an  irresistible  charm  seemed  soon  to  recall  him  to 
the  habitual  sphere  of  his  thoughts.  For  some  time  past, 
he  had  given  a  great  deal  of  his  leisure  to  the  perusal  of  works 
on  philosophy  and  political  economy;  he  had  also  bestowed 
much  time  on  the  study  of  languages,  so  that  he  was  able  to 
make  in  society  a  display  of  another  kind  of  merit  very  differ- 
ent from  that  with  which  he  obtained  the  applause  of  the  medi- 
cal profession. 

Beclard  was  benevolent  without  ostentation.  A  great  many 
students  received  from  him  benefits  of  every  kind,  and  he 
often  left  them  ignorant  whence  they  proceeded.  He  more 


16  LIFE  AND  WRITINGS  OP  BECLARD. 

than  once  abandoned  to  some  of  his  pupils  his  discoveries  and 
medical  opinions  which  soon  created  and  supported  their  repu- 
tation, and  who  afterwards  became  an  honour  to  their  illus- 
trious master.  He  zealously  aided  them  in  their  studies,  and 
encouraged  their  labours;  he  was  prodigal  of  the  wealth  of  his 
immense  erudition,  and  assisted  them  with  the  greatest  zeal 
in  the  cultivation  of  a  science  of  whicn  he  ardently  desired  to 
see  the  limits  extended. 

It  was  in  the  midst  of  so  many  useful  labours,  and  when  he 
began  to  enjoy  a  reputation,  which,  though  already  great, 
was  yet  onljT  dawning,  that  the  celebrated  professor  of  whom 
we  have  just  sketched  the  life,  was  seized  with  a  mortal  disease. 
On  the  6th  of  March,  1825,  an  erysipelitous  inflammation 
appeared  on  his  face,  which  soon  spread  over  the  integuments 
of  the  cranium.  From  its  first  appearance  a  cerebral  exalta- 
tion had  manifested  itself,  and  inspired  the  greatest  fears  for 
the  life  of  the  patient.  Notwithstanding  all  the  most  atten- 
tive cares,  the  malady  advanced  with  a  frightful  rapidity,  and 
on  the  16th  of  March,  Beclard  was  no  more. 

During  the  prolonged  delirium  which  terminated  his  life, 
his  intellect  had  acquired  an  astonishing  activity.  More  than 
once  we  observed  him,  while  in  this  state,  supposing  himself 
in  the  presence  of  a  large  audience,  and  developing  with  a  sur- 
prising energy,  ideas  which,  although  incoherent  in  them- 
selves, nevertheless  disclosed  the  powerful  and  elevated  mind 
which  gave  them  birth.  They  were,  in  a  manner,  the  last  ef- 
forts of  his  expiring  genius.  Finally,  after  a  long  and  painful 
agony,  he  breathed  his  last  in  the  arms  of  numerous  friends, 
that  were  bound  down  with  grief  at  his  bed  side.  As  soon  as 
the  news  of  his  death  reached  the  School  of  Medicine,  the  pu- 
pils who  for  several  days  previous  had  been  constantly  moving 
about  his  house,  in  order  to  learn  the  state  of  his  health,  these 
same  pupils  who  not  long  since  saluted  with  general  applause 
their  learned  and  modest  professor,  were  now  deeply  afflicted, 
and  bitterly  lamented  the  loss  of  so  valuable  a  teacher. 

On  the  17th  of  March,  1825,  the  day  of  his  burial,  two 
thousand  students  met  at  his  house,  and  would  not  permit 
other  hands  than  theirs,  to  carry  to  their  last  abode  his  pre- 


LITE  AND  WRITINGS  OP  BECLARD.  17 

cious  remains.  They  themselves  transported  the  body  of  Be- 
clard  to  the  church  of  Saint  Sulpice,  which  in  an  instant  was 
filled  with  SavanSj  professors,  and  students.  It  was  with  the 
same  eagerness,  that  the  students,  desirous  of  paying  a  last 
mark  of  respect,  admiration,  and  gratitude  to  their  teacher, 
carried  his  remains  to  the  burial  ground  of  Pere-La-Chaise. 
Those  who  could  not  have  the  honour  of  bearing  this  precious 
relicks,  followed  it  in  a  mournful  silence.  In  this  manner  it 
may  be  said,  that  he  had  a  more  imposing  attendance  than  the 
ordinary  and  paid  for  pompous  display,  which  surrounds  the 
funeral  car  of  the  rich  and  powerful. 

The  Royal  Academy  and  the  School  of  Medicine,  appointed 
a  man  of  known  eloquence  to  celebrate  the  last  honours  due  to 
the  manes  of  Beclard.  The  pupils,  on  their  side,  desirous  of 
giving  to  their  master  an  everlasting  pledge  of  their  sorrow, 
opened  immediately  a  subscription  to  erect  a  funeral  monu- 
ment to  his  memory.  The  School  of  Medicine  of  Paris,  and 
the  friends  of  Beclard,  imitated  the  generous  impulse  of  his 
younger  admirers,  and  we  soon  beheld  rising  over  his  grave, 
a  monument  which  will  long  recall  to  our  minds  the  talents  of 
Beclard,  the  universal  regret  of  which  he  was  the  object,  and 
the  noble  admiration  of  studious  youths  for  the  teacher  to 
whose  lessons  they  had  listened  with  so  much  eagerness;  and, 
who,  victim  as  he  was  of  his  ardour  for  acquirements  and  zeal 
for  public  instruction,  died  when  only  39  years  old,  and  when 
he  was  about  to  reach  the  zenith  of  his  glory.* 
Paris,  December  15th,  1826. 

*  While  the  School  of  Medicine  of  Paris  was  deploring'the  loss  of  Beclard, 
the  city  of  Angers,  not  less  afflicted  with  so  fatal  an  event,  wished  also  to 
honour  the  memory  of  a  man  who  had  done  so  much  for  the  glory  of  his 
country,  appointed  M.  David  his  countryman  and  friend,  and  equally  cele- 
brated in  his  art,  to  execute  in  marble  the  bust  of  the  rival  of  Bichat 


INTRODUCTION, 


§  1.  The  object  of  anatomy  is  the  study  of  organized  bo- 
dies ;  it  is  the  science  of  organization,  and  all  organized  beings 
are  the  subject  of  it.  Man,  the  most  complicated  of  all  be- 
ings, is  the  principal  subject  of  this  science.  The  special  aim 
of  Anatomy,  is  the  knowledge  of  the  human  body,  of  the 
different  parts  of  which  it  is  composed,  and  of  the  relations  of 
these  parts  with  respect  to  each  other. 

Comparative  anatomy,  which  might  have  been  very  well 
called  general  anatomy,  embraces  all  organized  bodies;  it  has 
for  its  object  to  seek,  by  comparison,  which  parts  they  possess 
in  common,  and  in  what  they  differ  from  each  other.  Phy- 
totomy  is  the  general  anatomy  of  vegetables,  that  of  animals 
is  called  Zootomy.  Anatomy  is  still  called  general,  when  it 
treats  of  a  class,  a  genus,  or  of  any  group  whatsoever  of  orga- 
nized beings ;  as  for  instance,  that  of  domestic  animals,  or 
veterinary  anatomy.  Special  anatomy  has  for  its  object  one 
single  species  of  organized  bodies ;  such  is  the  anatomy  of 
the  Elephant,  Horse,  Man,  &c. 

In  the  anatomy  of  man,  the  expression  general  anatomy 
has  another  acceptation,  which  will  be  mentioned  hereafter ; 
but  we  must  first  give  a  correct  idea  of  organization  in  gene- 
ral, and  of  the  bodies  which  are  endowed  with  it. 


SECTION  I. 

OP   ORGANIZED   BODIES. 

§  2.    The  endless  science,  called  Natural  Philosophy,  or 
physics,  the  science  of  nature,  treats  of  bodies  which  are  ex- 


20  INTRODUCTION. 

tended  and  moveable  beings.  They  may  be  considered  under 
two  different  points  of  view:  in  a  state  of  quiescence  and  in 
that  of  motion  or  action.  While  we  consider  objects  with  re- 
ference to  the  first  of  these,  we  particularly  observe  their  form, 
either  external  or  internal;  it  is  to  this  kind  of  study,  some- 
times termed  Morphology,  that  anatomy  belongs.  The  se- 
cond, to  which  is  generally  affixed  the  name  of  physics,  treats 
of  their  appreciable  changes,  i.  e.  of  their  phenomena  or 
movements,  either  as  masses,  or  as  molicules,  and  for  this  rea- 
son is  divided  into  two  principal  branches,  Mechanics  and 
Chemistry. 

§  3.  Bodies  which  have  common  or  general  properties, 
vary,  however,  in  many  respects.  Organization  and  life  con- 
stitute a  very  distinctive  character  which  divides  them  into 
two  very  different  series;  that  of  inorganic  bodies,  and  that 
of  such  as  are  organized  and  living. 

§  4.  It  would  be  useless  to  dwell  longer  on  inorganic  bo- 
dies, which  not  having  a  complicated  structure,  and  their  par- 
ticles being  entirely  independent  of  each  other,  can  not  con- 
sequently form  the  subjects  of  anatomical  consideration.  It 
is  sufficient  to  say,  that  the  movements  or  phenomena  of  mass- 
es executed  by  these  bodies,  the  object  of  mechanics,  are 
reproduced  with  a  regularity  and  constancy  which  permit  us 
not  only  to  observe  them,  to  produce  and  repeat  them  in  ex- 
periments, to  determine  the  laws  by  which  they  are  produced, 
but  to  submit  them  to  a  mathematical  analysis:  that  the  moli- 
cular  phenomena  of  these  same  bodies,  the  object  of  chemis- 
try, may  be  observed,  and  may  be  produced  or  determined  at 
pleasure  by  experiments;  that  certain  laws,  according  to 
which  they  are  produced,  may  also  be  deduced  from  actual 
observation  and  experiments;  but  that  these  phenomena  are 
yet  beyond  the  reach  of  calculation,  an  instrumental  science 
so  well  adapted  to  hasten  the  progress  of  those  to  which 
it  can  be  applied.  The  science  of  organization  and  of  life, 
is  nearly  confined  to  the  laws  of  observation. 

§  5.  Anatomy  treats  only  of  organized  and  living  beings. 
Besides  the  characters  which  they  possess  in  common  with 
inorganized  bodies,  they  have  others  which  are  peculiar  to 


OF   ORGANIZED   BODIES.  21 

themselves,  and  which  modify  the  former:  they  have  organi- 
zation and  life.  They  have  each  of  them  a  special  and  un- 
alterable form,  ordinarily  rounded,  which  is  apparently  owing 
to  the  fluids  they  contain.  Their  internal  form  or  structure, 
presents,  in  fact,  a  mixture  of  heterogeneous  parts,  some  solid, 
and  some  fluid.  The  solid  parts  are  called  organs,  which 
means  instruments,  because  of  the  action  they  exercise.  Their 
particles  are  intertwined,  interwoven  tissues,  their  arrange- 
ment also  being  called  texture;  they  are  areolar,  spongy,  or 
form  special  cavities,  which  contain  the  fluids.  These  parts 
may  be  generally  extended  or  elongated,  and  are  endowed 
with  elasticity.  When  these  parts,  or  organs  are  multiplied, 
as  is  commonly  the  case,  each  one  has  its  determinate  form, 
its  peculiar  texture,  and  its  proper  situation.  The  liquids,  or 
humours,  are  contained  in  the  solids,  and  penetrate  through 
every  part.  All  the  parts,  be  they  solid,  or  fluid,  are  held  in 
a  mutual  and  necessary  state  of  dependence  upon  each  other; 
and  it  is  from  their  union,  that  organized  bodies  originate. 
The  solids  and  fluids  have  an  analogous  composition;  they 
contain  much  water,  and  some  particular  combinations,  or 
proximate  materials,  and  may  be  almost  entirely  resolved  into 
gas.  The  substances  composing  them,  have  nothing  peculiar; 
they  are  also  to  be  found  in  the  inorganic  bodies  whence  they 
have  been  drawn,  and  the  line  of  demarcation,  which  distin- 
guishes organic  from  inorganic  solids,  consists  less  in  their 
nature  than  disposition.  It  is  erroneously  asserted,  that  the 
matter  of  organic  solids  differs  materially  from  inert  matter; 
for  oxigen,  hydrogen,  carbon,  and  in  a  great  many  azote,  and 
some  earthy  substances,  are  the  ultimate  elements  of  them 
all. 

It  is  to  this  peculiar  form,  to  this  structure,  common  to 
every  living  body,  this  areolar  or  net-work-like  tissue,  con- 
taining liquids  in  greater  or  less  abundance,  and  of  the  same 
nature  as  itself,  that  the  appellation  of  organization  has  been 
given. 

§  6.  We  understand  by  life,  the  phenomena  peculiar  to  or- 
ganized bodies  taken  as  a  whole.  Life  consists  essentially  in 
this  fact,  that  all  organized  bodies  during  a  determined  period, 


22  INTRODUCTION. 

are  centres  penetrated  by  foreign  substances  which  they  appro- 
priate to  themselves,  and  from  which  issue  others  that  become 
foreign  to  them.  In  this  movement  of  momentary  formation, 
the  matter  of  the  body  changes  continually,  but  its  form  still 
remains.  It  is  in  the  liquid  state  that  foreign  substances  pene- 
trate organized  bodies  ;  it  is  also  in  the  state  of  fluidity  that 
the  superfluous  molecules  are  cast  off.  The  liquids  and  solids 
are  incessantly  in  motion  during  organization;  the  liquids  tra- 
versing the  cavities  of  the  solids,  while  the  latter,  by  their 
dilatation  and  contraction,  produce  the  greater  part  of  the 
movement  of  the  former.  They  continually  change  the  con- 
stituent parts  of  one  into  the  other,  part  of  the  moving  fluids 
becoming  for  a  time  solids,  while  some  solid  parts  are  con- 
verted again  into  liquids,  which  exchange  perfectly  agrees 
with  the  analogy  of  their  composition.  Organized  bodies  ex- 
perience changes  during  the  whole  course  of  their  existence : 
and  from  the  moment  of  their  origin  they  increase  their  di- 
mensions and  density.  This  latter  kind  of  mutation  contin- 
ues until  the  structure  of  the  body  being  insensibly  altered, 
the  vital  movement  languishes  and  at  last  stops,  which  consti- 
tutes death;  after  this,  the  elements  which  composed  the  or- 
ganized body  separate,  and  form  new  combinations.  Each 
organized  body  having  not  only  its  external  form,  but  its 
own  peculiar  structure,  each  of  these  parts  contributes  by  its 
action  to  the  general  result.  The  appellation  of  function  is 
given  to  the  action  of  each  organ,  or  to  the  combined  actions 
of  several  having  the  same  end. 

Nutrition, a  function  comprising  absorption,  assimilation  and 
excretion,  of  which  we  have  just  spoken,  is  not  the  only  phe- 
nomenon common  to  organized  bodies;  generation  is  another 
equally  as  general,  and  without  which  species  could  not  exist, 
death  being  the  necessary  consequence  of  life.  Every  organ- 
ized and  living  body  originates  from  one  resembling  itself,  and 
each  produces  its  like.  In  order  to  accomplish  this  object,  a 
part  of  an  organized  body  which  had  already  attained  its  full 
size,  having  received  from  it  the  materials  for  its  own  growth, 
separates  from  it  and  produces  a  being  in  every  respect  similar 
to  its  parent,  and  presenting  the  same  phenomena.  This  part 


0V   ORGANIZED  BODIES.  23 

is  called  germ  as  long  as  it  forms  a  portion  of  the  body  of  the 
parent.  This  latter  general  phenomenon  is  only  a  consequence 
of  the  former.  As  long  as  the  germ  makes  a  part  of  the  body 
of  the  parent,  it  is  nourished  and  grows  as  one  of  its  organs; 
its  separation  constitutes  a  kind  of  excretion. 

Most  of  the  organized  bodies  also  reproduce  parts  of  which 
they  may  be  deprived;  they  likewise  repair  to  a  certain  ex- 
tent the  lesions  that  they  experience. 

The  mass  of  individuals  born  of  the  same  parents,  and  of 
those  which  resemble  them  as  much  as  they  themselves  are 
like  to  each  other,  constitute  a  species.  External  circum- 
stances, such  as  the  atmosphere,  food  &c.,  as  they  are  more  or 
less  favourable,  influence  organization  and  its  phenomena: 
hence  results  a  greater  or  smaller  degree  of  perfection  in  the 
development,  and  differences  of  similitude,  generally,  some- 
what limited  between  the  individuals  of  the  same  species;  and 
this  constitutes  the  varieties.  From  this  also  results  various 
individual  alterations  in  organized  and  living  bodies:  these  al- 
terations of  organization  and  of  its  phenomena  constitute 
disease. 

This  series  of  phenomena  is  common  to  all  organized  bo- 
dies, and  may  be  summed  up  in  the  following  manner:  The 
origin  is  derived  from  a  being  similar  to  itself,  the  end  ter- 
minates by  death,  the  maintenance  of  the  individual  is  ob- 
tained from  nutrition,  the  continuance  of  the  species  by  gene- 
ration; in  a  word,  it  is  the  reception  of  an  action  of  momentary 
formation,  exercised  in  a  body  which  has  received  its  princi- 
ple from  a  parent,  and  transmits  the  same  to  its  offspring,  that 
is  called  life. 

The  two  characteristic  marks,  which  essentially  distinguish 
organized  and  living  bodies,  and  which  are  common  to  all  and 
peculiar  to  them  alone,  are  organization  and  life. 

§  7.  The  form  and  the  action  of  organized  and  living  bodies, 
organization  and  life,  are  so  closely  connected,  that  whenever 
we  observe  the  one  we  may  be  certain  of  the  existence  of  the 
other;  indeed  the  one  always  pre-supposes  the  other.  We 
never  observe  life  but  in  organized  bodies,  and  we  never  ob- 
serve organization  but  in  living  bodies.  In  fact,  in  order  that 
5 


24  INTRODUCTION. 

life  might  exist,  it  was  necessary  that  there  should  be  solids 
to  preserve  the  form  and  fluids  to  keep  up  motion,  in  a  word, 
an  organization;  and  inprder  that  the  latter  should  be  enabled 
to  exist  in  the  midst  of  causes,  all  tending  to  its  destruction, 
it  was  requisite  that  there  should  be  a  continual  motion  and 
renewal  of  its  parts.  Organized  bodies  are  born  alive  from 
bodies  alike  to  themselves,  i.  e.  they  are  viviparous;  in  all, 
and  during  the  whole  term  of  their  existence,  the  vital  phe- 
nomena are  in  exact  proportion  to  the  state  of  organization; 
and  when  this  latter  is  altered,  either  from  the  mere  fact  of 
possessing  life,  or  from  accidental  circumstances,  life  lan- 
guishes and  ceases,  and  organization  is  destroyed  by  the  che- 
mical action  of  its  own  elements.  Among  all  those  who  ob- 
serve the  phenomena  of  nature,  no  one  has  ever  been  able  to 
detect  matter  in  the  very  act  of  organizing  itself,  or  life  estab- 
lishing itself,  either  spontaneously  or  by  external  causes,  else- 
where than  in  bodies,  already  living  and  organized.  Life,  in 
fact,  does  not  solely  consist  in  a  reunion  of  molecules  which 
were  before  separated,  as  occurs  in  the  case  of  chemical  at- 
traction, nor  simply  in  an  expulsion  of  the  elements  previous- 
ly combined,  as  in  that  which  is  produced  by  the  repulsive 
action  of  caloric;  but  in  a  movement  of  temporary  formation, 
in  which  some  elements  remain  united,  which  would  sepa- 
rate should  life  cease,  and  in  which  the  elementary  parts  are 
separated,  without  the  action  of  caloric;  now,  this  vital  action 
exists  only  in  organized  bodies.  This  close  and  reciprocal 
connexion  of  organization  and  life,  is  the  reason  why  they 
have  been  by  turns  considered  as  being  the  cause  or  the  ef- 
fect of  each  other.  This,  doubtless,  is  wrong;  organization 
and  life  are  a  complex  idea,  which  should  no  more  be  divided, 
(unless  abstractedly),  than  these  two  things  themselves,  which 
are  inseparable.  Life  is  organization  in  action,  or,  according 
to  the  happy  expression  of  Stahl,  is  the  organism.  The  ob- 
ject of  this  work,  however,  being  the  examination  of  orga- 
nization in  a  state  of  rest,  life  will  be  merely  alluded  to.* 
§  8.  Organized  bodies  having  a  heterogeneous  structure, 

*  See  Richerand's  Elements  of  Physiology. 


OF    ORGANIZED    BODIES.  25 

their  history  is  composed  of  that  of  their  various  parts;  and 
and  it  is  properly  this  study  which  is  the  object  of  anatomy. 
The  physical  state  of  these  bodies  does  not  only  embrace  me- 
chanical or  chemical  phenomena,  but  also  those  which  belong 
to  them  in  proper,  and  which  are  not  possessed  by  inorganic 
bodies,  viz:  nutrition  and  generation,  i.  e.  the  organic  or  vi- 
tal actions.  These  particular  physical  laws  assume  the  name 
of  physiology. 

Anatomy*  then  may  be  defined  the  knowledge  of  organized 
bodies,  or  the  science  of  organization.  According  to  its  ety- 
mology, this  word  has  another  signification:  it  simply  means 
dissection;  but  it  has  been  consecrated  by  custom,  and  it  is 
preferred  to  the  words  morphology,  organology,  (a  discourse 
on  form,  organs),  that  have  been  proposed  as  substitutes. 
Anatomy,  in  fact,  is  a  science  of  mere  observation,  and  dis- 
section is  the  principal  means  by  which  we  expose  the  parts 
of  organized  bodies  in  order  to  be  able  to  observe  them. 

Physiologyt  is  the  knowledge  of  the  phenomena  of  orga- 
nized bodies,  or  the  science  of  life;  it  is  also  sometimes  call- 
ed Zoonomy,  (laws  of  life,)  and  biology,  (discourse  on  life). 
Physiology,  like  anatomy,  is  a  science  of  observation;  but  it 
treats  of  the  phenomena  of  organized  and  living  bodies. 

Anatomy  and  physiology  are  closely  connected;  having 
been  taught  by  observation,  that  organization  and  the  pheno- 
mena of  life  are  always  in  a  reciprocal  relation,  we  may  infer 
the  condition  of  the  one  by  the  state  of  the  other. 

§  9.  Organized  and  living  bodies,  the  subjects  of  anatomy 
and  physiology,  are  divided  into  inanimate  beings,  or  vegeta- 
bles, and  animals  or  animated  beings;  this  division  is  derived 
from  the  well  marked  difference  existing  between  animals 
and  vegetables  of  a  complicated  organization,  but  is  very  little 
so,  among  those  the  organization  of  which  is  the  simplest  of 
all. 

§  10.  The  most  complicated  vegetables  are  generally  form- 
ed of  two  distinct  parts,  separated  by  a  median  horizontal  line, 
one  descending,  and  contained  in  the  earth,  is  the  root;  while 


*  From  hva.Ttfj.vcDy  I  dissect. 

f  From  <j>y<n?,  nature,  and  x&>o?,  discourse. 


INTRODUCTION. 

the  other  ascending  and  surrounded  by  the  atmosphere,  is  the 
stem,  body,  or  tree  which  bears  the  leaves  and  flowers.  Their 
structure  consists,  simply,  in  an  areolar  tissue,  vessels  and  spi- 
ral tubes,  which  are  called  tracheae.  They  possess  no  other 
organs  than  those  of  nutrition  and  generation.  Their  most 
important  and  vital  parts  are  all  situated  externally.  Their 
chemical  composition  is  rather  simple;  nitrogen  is  seldom  met 
with  in  them,  and  if  found  at  all,  it  exists  only  in  some  par- 
ticular part.  Their  vital  action  is  confined  to  their  growth 
and  reproduction.  Their  nutrition,  the  materials  of  which 
are  drawn  from  the  earth  and  atmosphere,  from  water  and  air, 
consists  in  an  absorption  induced  by  the  roots,  by  a  move- 
ment of  translation  that  the  liquids  experience  in  the  vessels 
of  the  stem,  and  in  a  kind  of  respiration  which  occurs  prin- 
cipally in  the  leaves:  in  these  various  actions  vegetables  re- 
tain hydrogen  and  carbon,  little  or  no  nitrogen,  and  ex- 
hale the  superfluous  oxygen.  Their  reproduction  is  induced 
in  divers  manners.  There  is,  moreover,  in  the  organization 
of  vegetables,  a  very  great  diversity,  which  can  not  be  pro- 
perly treated  of  in  this  work. 

OF   ANIMALS. 

§11.  Animals,  at  the  head  of  which  is  man,  who 
closely  resembles  some  of  them,  besides  the  general  charac- 
ters of  organized  bodies,  have  others  which  are  peculiar  to 
themselves,  which  consequently  distinguish  them  from  vege- 
tables, and  which  have  an  influence  on,  and  modify  the  for- 
mer. But  animals  are  so  very  different  from  each  other,  that 
their  characters,  which  may  be  said  to  be  common,  are  nei- 
ther very  numerous,  nor  very  distinct.  The  following  are 
those  peculiar  to  animals,  some  few  of  which  are  common  to 
all,  and  others  are  more  or  less  general. 

Besides  the  rounded  form  which  belongs  generally  to  all 
organized  beings,  we  observe  that  the  greater  number  of  ani- 
mals are,  at  least  externally  symmetrical  and  divided  by  a 
median  vertical  line,  into  two  lateral  and  similar  halves,  and 
that  their  length  in  this  direction,  is  greater  than  in  any  other 
of  their  dimensions.  The  liquids  greatly  predominate  over 


OP   ANIMALS.  27 

the  solids.  The  areolar  or  cellular  tissue,  which  forms  the 
greater  part  of  the  body,  is  very  soft  and  contractile.  The  body 
is  traversed  by  an  internal  cavity,  in  which  the  aliments  are 
received.  This  cavity  as  well  as  the  exterior  surface,  is  invest- 
ed with  a  membrane  or  skin  which  limits  and  envelops  the 
remainder  of  the  body.  There  are  in  many  animals  circulating 
vessels  which  convey,  in  certain  determined  directions,  the 
nutritive  substance  found  in  the  intestine,  into  every  part  of 
the  body;  organs  of  respiration,  in  which  this  matter  is  sub- 
mitted to  the  action  of  the  atmosphere,  and  secretory  organs, 
in  which  a  part  of  this  matter  is  separated  from  the  mass. 
They  have  genital  organs  which  generally  consist  in  a  cavity 
from  which  the  germs  are  detached  and  expelled.  Finally, 
in  most  animals,  there  are  muscles  to  execute  the  apparent 
movements,  senses  to  receive  the  impressions  of  external  ob- 
jects, and  a  nervous  system  consisting  in  cords  or  filaments, 
having  one  of  their  extremities  immersed  and  expanded  in  the 
integuments  and  muscles,  and  the  other  swelling  into  enlarge- 
ments or  ganglia  more  or  less  considerable. 

§  12.  The  solids,  or  organs  of  animals,  have  for  their  prin- 
cipal base  the  cellular  tissue,  a  soft,  extensible  and  contractile 
substance,  easily  permeated  by  liquids.  Condensed  on  the 
two  surfaces  of  the  body,  it  forms  on  the  exterior,  the  skin, 
and  on  the  interior,  the  mucous  membranes  or  the  internal 
skin.  It  is  this  very  same  membrane,  the  skin,  variously  dis- 
posed, which  constitutes  the  organs  of  respiration,  secretion 
and  generation.  It  also  forms  the  senses.  Hollowed  into 
ramified  canals,  in  the  parietes  of  which  it  possesses  a  consi- 
derable consistence,  the  cellular  tissue  constitutes  the  vessels. 
This  same  substance  variously  modified,  without  losing  how- 
ever its  distinctive  characters,  forms  also  several  other  kinds 
of  organs  in  animals.  The  muscular  fibre  constitutes  a  second 
kind  of  solid,  essentially  differing  from  the  cellular  tissue,  be- 
cause in  the  midst  of  this  soft  substance  which  forms  the  com- 
mon mass,  linear  series  of  microscopic  globules  are  to  be  ob- 
served; this  muscular  fibre  contracts  whenever  irritated.  The 
substance  of  the  nerves  is  formed  also  of  globules,  but  different 
from  those  which  compose  the  muscles;  it  transmits  to  nervous 


28  INTRODUCTION. 

centres  the  impressions  received,  and  to  the  muscles  the  in- 
fluence of  the  same  nervous  centres. 

The  animal  fluids  or  humours  are  numerous  and  in  abun- 
dance. In  most  animals  there  is  a  liquid  in  circulation  in  the 
vessels;  it  is  the  blood,  which  is  the  principal  and  most  im- 
portant part  of  the  nutritive  liquids;  other  liquids  are  absorbed 
from  the  surfaces  or  the  mass  of  the  body  itself,  and  others, 
finally,  are  secreted  or  separated  from  the  blood.  This  latter 
essentially  consists  in  a  very  abundant  serous  vehicle,  in  which 
are  immersed  microscopic  bodies  similar  to  those  observed  in 
the  solids.  The  composition  of  the  blood  is  altogether  analo- 
gous to  that  of  the  solid  parts,  and  a  simple  change  of  state,  or 
some  small  change  in  the  proportions  of  the  componing  ele- 
ments, are  sufficient  to  produce  the  conversion  of  the  liquids 
into  the  solids. 

The  ultimate  anatomical  elements  of  the  humours  and  of 
the  organs  of  animals,  appear  then  to  be  simply  an  amorphous 
substance,  liquid  in  the  blood  in  which  it  constitutes  the  serum 
or  the  albumen,  and  concrete  in  the  organs  in  which  it  con- 
stitutes the  cellular  tissue,  and  a  substance  under  a  globular 
form,  or  globules  freely  floating  in  the  blood,  and  stationary  in 
the  organs  where  they  form  the  muscular  fibre  and  the  nervous 
substance.  The  chemical  composition  of  the  animal  body  is 
more  complicated  than  that  of  vegetables,  and  consist  in  more 
volatile  elements.  This  is  the  reason  why  nitrogen  enters  into 
their  composition  as  a  very  essential  part,  and  is  mixed  with 
the  other  general  elements  of  the  organization.  Lime  is  the 
earthy  element  most  generally  found  in  it. 

§  13.  The  general  organic  phenomena,  such  as  nutrition  and 
generation,  are  met  with  in  animals,  but  modified  by  the  phe- 
nomena which  are  peculiar  to  them.  Nutrition,  instead  of  be- 
ing the  result  of  external  absorption  alone,  is  induced  at  the 
same  time,  and  principally  from  an  internal  absorption  which 
occurs  in  the  intestinal  cavities.  The  nutritive  fluid  taken  up 
in  the  intestines  is  submitted  to  the  action  of  the  atmosphere; 
the  result  of  this  respiration,  is  a  production  of  water  and  car- 
bonic acid,  which  result  is  precisely  the  contrary  of  what  hap- 
pens in  vegetables.  Besides  this,  the  nutritive  liquid  needs 


OF    ANIMALS.  29 

to  be  continually  purified  from  all  superabundant  and  extrane- 
ous substances,  by  means  of  secretion.  They  occur  on  the  ex- 
ternal and  internal  surfaces,  sometimes  through  the  gaping 
orifices  of  vessels  opening  on  large  surfaces,  which  permit  the 
secreted  liquid  to  ooze  out;  while  at  others  it  is  from  the  bot- 
tom of  small  cavities  formed  in  the  skin  or  in  the  mucous 
membrane,  that  we  perceive  this  percolation;  again,  we  ob- 
serve the  circulating  vessels  communicating  with  proper  ves- 
sels or  ramified  excretory  canals,  which  are  also  formed  by  the 
envelope  of  the  body,  and  which  pour  out  the  secreted  liquid. 
Among  the  liquids  which  are  the  result  of  secretions,  some 
are  necessary  to  the  exercise  of  functions,  others  are  entirely 
rejected  as  superfluous  and  extraneous,  which  constitutes  a  kind 
of  depuration.  The  nutritive  fluid  continually  supplied  by  in- 
testinal absorption,  maintained  in  a  proper  state  by  respira- 
tion and  secretions,  is  sent  into  every  part  of  the  body,  und 
there  effectuates  nutrition,  a  wonderful  process  in  which  this 
fluid  is  decomposed  in  such  a  manner,  that  in  every  part  of 
the  body  a  portion  of  the  blood  becomes  solid,  and  constitutes 
an  integral  part  of  the  organ;  when  at  the  same  time,  and  in 
every  part  also,  a  portion  of  the  organs  returns  to  a  liquid  state, 
and  again  enters  into  the  vortex  of  the  circulating  fluid. 
Generation,  or  the  production  of  a  new  being,  is  so  diversified 
in  its  modes,  that  it  presents  no  distinctive  character  peculiar 
to  animals  and  common  to  them  all.  The  separation  of  the 
sexes,  which  is  subordinate  to  motion,  is  in  fact,  neither  peculiar 
nor  common  to  the  animal  kingdom.  Animals  possess  also  the 
power  of  reproducing  by  a  kind  of  vegetation,  certain  parts 
when  they  are  removed,  although  in  a  smaller  degree  than 
vegetables. 

§  14.  Muscular  motion,  sensations  and  nervous  action,  give 
to  animals,  in  a  manner,  a  new  life.  These  functions  have 
consequently  received  the  appellation  of  animal  life,  in  op- 
position to  the  other  functions  called  organic  or  vegetative 
life.  The  impressions  produced  by  external  agents  on  the  or- 
gans of  sensations,  i.  e.  on  the  external  or  internal  skin,  or  in 
a  peculiar  manner  on  some  of  their  organized  parts,  induce  in 
these  organs  actions  which  are  transmitted  by  the  nerves  to 


30  INTRODUCTION. 

the  central  masses  of  the  nervous  system.  There  does  not 
exist  a  single  part  of  the  body,  which,  under  certain  circum- 
stances, may  not  be  the  seat  of  some  sensation.  When  the  ani- 
mal has  received  a  sensation,  and  that  excites  in  him  a  voli- 
tion, it  is  also  through  the  nerves  that  this  volition  is  trans- 
mitted to  the  muscles,  the  contractions  of  which  produce  the 
movements  of  the  animal. 

The  nervous  action  is  not  confined  to  transmitting  the  im- 
pressions received  by  the  senses  and  the  volition  to  the  mus- 
cles; for,  the  nervous  central  masses  are  also  the  organs  of  in- 
stinct and  of  the  cerebral  functions. 

The  functions  of  which  we  speak  are  not  only  superadded 
in  animals  to  the  organic  or  vegetative  functions,  but  they  sin- 
gularly modify  the  exercise  of  the  latter.  Thus  in  nutrition, 
the  introduction  of  the  aliments  is  generally  produced  by  mus- 
cular movements;  the  muscular  fibres  which  form  a  coat  to 
the  intestines,  is  also  the  cause  that  the  aliment  they  contain  is 
moved  on  in  this  tube;  it  is  also  a  set  of  muscles,  which,  in 
many  animals,  are  placed  at  the  point  and  centre  of  reunion 
of  all  the  vessels,  which  propel  the  blood;  and  it  is  muscles 
also  which  induce,  by  their  movement,  the  introduction  into 
and  diffusion  of  air  in  the  respiratory  organ.  There  are 
senses  placed  at  the  entrance  of  the  organs  of  nutrition. 
Nerves  are  also  distributed  to  the  organs  of  nutrition,  and  al- 
though in  an  ordinary  state  these  nerves  transmit  neither 
sensation  nor  volition,  and  movements  are  suddenly  deter- 
mined in  them  by  impressions  or  irritations,  nevertheless,  in 
powerful  affections  of  the  nervous  centres,  the  movements  are 
interrupted,  and  in  a  pathological  state  these  functions  are  ac- 
companied with  sensations.  Generation  is  like  nutrition,  mo- 
dified in  its  actions  by  the  animal  functions. 

§  15.  There  is,  in  fact,  between  all  the  organs,  and  between 
all  the  functions  of  animals,  a  connexion  which  exists  in  all 
organized  and  living  bodies,  but  which  is  still  more  remarka- 
ble in  animals,  and  especially  in  some  of  them.  In  organized 
beings,  which  possess  only  nutrition  and  reproduction,  the 
latter  of  these  functions  is  the  consequence  of  the  former. 
In  animals  which  enjoy  motion  and  sensation,  nutrition  must 


OF   ANIMALS.  31 

be  executed  by  digestion,  for  the  animal  could  not  at  the  same 
time  possess  the  power  of  locomotion,  and  be  fixed;  genera- 
tion in  this  case  is  sexual.  In  proportion  as  each  order  of 
functions  becomes  more  complicated,  the  organs  superadded 
to  those,  whose  existence  is  more  general,  hold  the  for- 
mer under  their  control.  Thus,  for  instance  in  the  order  of 
the  nutritive  functions,  the  circulation,  and  in  the  latter,  the 
action  of  the  heart,  which  is  not  as  common  as  the  other  nu- 
tritive phenomena,  keep,  when  they  exist,  all  the  others  under 
their  influence.  In  the  same  manner,  in  the  animal  functions, 
the  action  of  the  nervous  centres  holds  in  subjection  those 
phenomena,  whose  existence  is  more  generally  met  with  in 
organized  beings.  The  animal  functions  hold  under  theirs 
all  the  nutritive  and  reproductive  ones,  but  these  latter,  in 
their  turn,  keep  the  former  in  a  similar  state;  the  organs  of 
animal  functions  having  to  be  nourished,  in  order  to  fulfil 
their  own,  and  these  latter  inducing  the  exercise  of  the  organs 
of  the  vegetative  functions.  So  that,  in  animals  whose  orga- 
nization is  very  much  developed,  life  seems  essentially  to  re- 
sult from  the  reciprocal  action  of  the  central  organ  of  the  ve- 
getative functions,  and  from  the  principal  organ  of  the  animal 
functions,  from  the  circulation  and  the  nervons  action,  or  in 
other  words,  from  the  action  of  the  blood  on  the  nervous  sys- 
tem, and  from  the  nervous  system  on  the  organs  which  propel 
the  blood.  The  other  phenomena  maintain  these  two  princi- 
pal actions,  which  may  be  considered  as  the  two  essentially 
vital  functions  of  animals. 

§  16.  To  all  these  characters,  the  first  very  general  and 
common,  and  the  second  much  less  so,  we  must  add  the  disor- 
ders of  the  organization,  and  the  phenomena  of  life,  i.  e.  dis- 
eases much  more  frequent  in  animals  than  in  vegetables;  and 
the  reason  of  this  may  be  easily  found  in  the  complication  of 
their  organization,  in  the  concatenation  of  all  the  parts  with 
each  other;  and  in  the  operation  of  central  and  predominating 
organs,  the  action  of  which  can  not  be  disturbed  without  the 
whole  economy  suffering  by  it.  Hence  the  study  of  the  causes 
and  external  bodies  which  influence  the  animal  organization 

in  a  hurtful  or  beneficial  manner,  and  the  art  of  preserving  or 
6 


32  INTRODUCTION. 

restoring  health  by  the  well  directed  employment  of  external 
agents,  or  the  science  of  medicine. 

Such  are  the  most  general  characteristics  of  animals;  but 
these  beings  present  in  their  organs  and  functions  a  multitude 
of  varieties  or  of  degrees  of  complication,  that  it  is  important 
to  examine. 

§  17.  The  external  form,  or  configuration,  which  may 
give  an  idea  of  the  structure,  of  which  it  is,  in  a  manner, 
the  outline,  presents  the  following  varieties.  Some  animals 
are  punctiform  or  globular,  as  the  monads;  others  are  fili- 
form as  the  vibrio;  some  are  flat,  resembling  a  small  mem- 
brane, such  are  the  cyclida;  finally,  others  belonging,  like 
the  preceding  ones  to  the  class  of  infusoria,  have  no  deter- 
mined form,  their  configuration  changing  at  every  moment  in 
the  most  singular  manner,  these  are  the  protei.  These  ele- 
mentary forms,  which  pertain  to  all  the  animals  that  are  the 
simplest  in  their  composition,  are  to  be  found  in  some  indi- 
viduals of  a  nobler  order,  and  in  certain  parts  of  all  others. 
The  same  is  the  case  with  the  stellated  or  radiated  form  which 
belongs  to  a  certain  number  of  classes  of  animals,  and  that 
we  meet  with  in  various  parts  of  those  animals  which  have  a 
very  different  external  configuration. 

The  radiated  form  begins  to  be  observed  in  the  order 
rotiferce,  and  other  polypi;  in  the  acalepha  and  echinoder- 
rnata,  the  radiated  form  is  not  confined  to  their  exterior, 
which  resembles  a  radiated  flower,  or  to  a  star,  but  all  the 
parts  are  arranged  around  an  axis,  and  on  a  greater  or  small- 
er number  of  radii.  In  some  other  animals  the  axis  being 
longer,  the  radiated  form  becomes  cylindrical.  The  cylindri- 
cal echinodermata,  intestinal  worms  and  annelides  establish 
this  passage  from  the  radiated  form,  of  which  they  still  pre- 
serve some  slight  marks,  to  the  symmetrical  form  and  articu- 
lar arrangement  which  they  likewise  possess;  and  the  tunicata 
the  transition  from  the  radiated  to  the  symmetrical  form  with- 
out articulation. 

The  symmetrical  form  is  to  be  observed,  with  some  few  ex- 
ceptions, in  all  other  animals.  In  those  which  have  this  con- 
figuration, the  body  is  divided  into  two  lateral  parts,  or  into 


OP   ANIMALS.  33 

two  similar  sides  by  a  median  line;  but  it  is  subdivided  into 
two  others  very  different.  In  the  mollusca  the  body  is  not 
divided  into  segments,  and  there  are  no  articulated  feet,  for 
they  are  inarticulate.  The  other  symmetrical  animals,  on  the 
contrary,  are  articulate,  i.  e.  their  body  is  divided  into  seg- 
ments, moveable  upon  each  other,  and  their  limbs,  when  they 
have  any,  are  divided  into  several  parts  by  articulations.  We 
already  discover  the  articular  arrangement  in  the  cirrhipoda, 
which  properly  belong  to  themollusca;  the  rudiments  of  it  are 
also  perceived  in  iheci/lindricalechinodermata^nd  in  worms, 
but  this  kind  of  form  more  particularly  belongs  to  the  annelides, 
insecta,  Crustacea,  and  arachnides,  which  for  this  reason  are 
called  articulated  animals,  and  to  all  the  vertebrated  animals. 
Thus  we  may  in  conclusion  refer  the  animal  forms  to  the  fol- 
lowing: the  symmetrical  or  binary  form,  with  or  without  ar- 
ticulations, the  radiated  form,  and  the  simple  forms  of  a  glo- 
bule, of  a  filament,  &c.  &c. 

§  18.  The  external  configuration  of  animals  presents  also 
other  differences.  The  body  is  divided  into  a  trunk,  a  central 
part,  which  contains  the  organs  essential  to  life,  or  in  other 
words,  the  viscera,  and  into  appendages,  parts  generally  des- 
tined for  motion  and  sensation.  The  trunk  is  divided  into  the 
trunk  proper,  or  the  middle  part,  and  into  the  extremities, 
the  head  and  tail;  the  trunk  itself  is  sometimes  subdivided 
into  abdomen  and  thorax.  The  head  is  the  part  which 
contains,  besides  the  mouth,  the  principal  nervous  expansion, 
or  the  brain,  and  the  organs  of  the  special  senses.  The  tho- 
rax, in  the  articulated  animals,  is  the  part  of  the  trunk  to 
which  the  limbs  are  attached;  in  the  vertebrata  it  is  that  which 
contains  the  heart  and  lungs.  The  abdomen  always  contains 
the  principal  organs  of  digestion  and  of  generation.  These 
various  parts  of  the  trunk,  which  do  not  all  constantly  exist, 
present  diverse  varieties. 

In  the  radiated  animals,  in  the  acephalous  mollusca,  and 
in  the  intestina  and  annelides,  the  trunk  is  reduced  to  its  mid- 
dle part,  consists  of  a  single  cavity,  which  contains  all  the  or- 
gans. In  the  cephalous  mollusca  there  is  a  distinct  head; 
the  same  is  the  case  with  the  insecta,  Crustacea,  and  arach- 


34  INTRODUCTION. 


j  which  have  besides  a  thorax,  sometimes  distinct  from 
the  head  and  abdomen,  and  at  others  confounded  with  one  or 
both  parts  of  the  trunk.  In  the  vertebrated  animals  the  head 
is  always  distinct,  but  the  thorax  is  sometimes  confounded 
with  the  abdomen.  The  appendages  present  also  different  va- 
rieties; in  the  infusoria  there  are  small  ones  called  cilias. 
The  radiated  animals  have  the  mouth  surrounded  with  appen- 
dages called  tentacula,  which  are  destined  for  motion  and  sen- 
sation. The  same  is  observed  in  some  mollusca,  which  have 
sensitive  tentacula,  and  other  fleshy  productions,  called  arms 
or  feet,  for  the  purpose  of  locomotion.  The  crustaceous  ani- 
mals and  insects  have  antennae,  articulated  filaments,  of  very 
diversified  shapes  affixed  to  the  head,  and  which  seem  to  be 
organs  of  sensation.  The  same  may  be  said  of  their  palpi, 
that  are  found  also  in  the  arachnida.  The  lateral  appendages 
are  double,  essentially  intended  for  motion,  and  are  called 
limbs  when  they  are  articulated,  the  rudiments  of  them  may 
be  observed  in  the  cirrhopoda  and  in  the  setigerous  an- 
nelides;  they  are  found  in  great  number  in  the  myriapoda; 
they  are  also  found  in  a  considerable,  but  variable  number,  in 
the  Crustacea;  there  are  eight  in  the  arachnides,  and  six  in  the 
true  insecta,  which  possess,  for  the  most  part,  either  four  or 
two  wings.  In  the  vertebrata,  there  are  never  more  than  four 
limbs. 

§  19.  The  organs  of  nutrition  present  a  very  great  diver- 
sity. In  the  most  simple  animals,  the  infusoria,  this  function 
consists  solely  in  an  external  absorption  or  imbibition,  the  ma- 
terials of  which  penetrates  every  part  of  the  body  of  the  ani- 
mal, and  is  immediately  assimilated  and  afterwards  excreted  ; 
this  simplicity  of  organization  is  to  be  found  in  some  intes- 
tinal worms,  and  in  some  of  the  acalepha. 

In  animals,  a  degree  higher  in  the  scale,  we  find  an  intesti- 
nal cavity  excavated  in  the  substance  of  the  body,  and  from 
this  moment  absorption  is  performed  by  both  surfaces,  and 
especially  by  the  internal  one.  This  simple  cavity  is  observ- 
ed in  some  polypi.  At  a  still  higher  degree,  this  cavity  con- 
sists of  a  membranous  sac,  distinct  from  the  mass  of  the  body, 
formed  by  a  membrane  or  internal  skin,  continuous  and  analo- 


OF  ANIMALS.  35 

gous  to  the  external  one.  The  animals  which  present  the 
first  rudiments  of  the  arrangement,  are  also  the  polypi  and 
acalepha  and  some  intestinal  worms.  In  other  animals  of  the 
same  class,  the  gastric  cavity  has  prolongations  extending  into 
the  mass  of  the  body,  in  order  to  provide  it  with  nourishment. 
In  some  acalepha  and  intestinal  worms,  the  stomach  is  want- 
ing, and  there  are  only  ramified  prolongations  opening  on  the 
external  surface.  In  all  these  first  appearances  of  an  intestinal 
cavity,  that  cavity  is  confined  to  a  mere  elongated  sac,  having 
one  single  opening.  Several  of  the  echinodermata,  and  in- 
testinal worms  have  a  distinct  intestinal  canal,  a  mouth  and  an 
anus,  an  arrangement  which  is  to  he  observed  in  all  the  higher 
classes,  in  which  this  canal,  more  or  less  enlarged,  or  more  or 
less  contracted,  is  extended  through  the  body.  The  existence 
of  this  canal  is  perceived  at  the  same  time  with  the  cylindri- 
cal and  elongated  form  of  the  body. 

The  mouth  presents  several  varieties,  the  principal  of  which 
are  those  of  a  simple  orifice,  or  an  opening  furnished  with 
muscles,  and  sometimes  with  hard  parts,  but  intended  for  suc- 
tion only;  or  an  orifice  surrounded  with  muscles,  and  furnish- 
ed with  hard  parts  to  divide  the  aliment. 

§  20.  In  many  of  the  inferior  animals,  the  nourishing  fluid, 
absorbed  by  the  parietes  of  the  intestines,  which  are  either 
simple  or  elongated  and  extended  in  the  body  by  ramified  ap- 
pendages, is  carried  immediately  by  the  areolar  substance  into 
every  part  of  it.  This  is  the  case  with  all  the  radiated  ani- 
mals, and  with  the  immense  class  of  insects.  In  fact,  in  no 
insect  are  there  any  vessels,  and  the  nourishing  fluid  must 
pass  by  imbibition  from  the  intestine  into  every  part  of  the 
body;  there  is  only  a  dorsal  vessel  which  appears  to  be  the 
rudiment  of  a  heart,  but  there  are  no  branches  for  circula- 
tion. 

In  animals  of  a  still  higher  class,  the  nourishing  liquid,  ab- 
sorbed by  the  parietes  of  the  intestines,  circulates  in  close  ves- 
sels, the  minute  ramifications  of  which,  only  permit  the  nour- 
ishing molecules  to  pass  into  the  substance  of  the  body.  The 
vessels  which  go  from  the  centre  of  the  circulation  to  all  the 
other  parts  are  called  arteries;  those  which  bring  back  the  li- 


36  INTRODUCTION. 

quids  from  every  part  of  the  body  to  this  same  centre,  are 
named  veins;  at  the  point  of  reunion  of  both,  is  to  be  found  in 
many  animals  a  fleshy  organ,  the  heart,  which  aids  by  its  con- 
tractions the  motion  of  the  liquid,  and  which,  like  the  vessels, 
is  more  or  less  complicated.  We  find  the  first  rudiments  of 
vessels  in  some  intestinal  worms,  and  the  first  rudiment  of  a 
heart  in  insects. 

In  the  annelides,  the  only  invertebrated  animals  which  have 
red  blood,  there  are  arteries  and  veins  for  the  circulation,  but 
there  is  simply  a  rudiment  of  a  heart.  In  the  arachnides  tra- 
cheariae,  the  organs  of  circulation  are  not  any  better  marked 
than  in  the  insects;  but  in  others,  such  as  the  pulmonariae,  there 
is  a  heart  or  great  dorsal  vessel  and  branches  on  each  side. 

The  Crustacea  present  more  distinctly  a  heart;  in  some  it  is 
elongated  into  a  large  fibrous  vessel  which  extends  all  along 
the  tail,  giving  branches  on  both  sides,  and  which  recall  to 
our  minds  the  dorsal  vessel  of  insects;  but  in  other  Crustacea, 
there  is  a  dorsal  ventricle,  a  great  abdominal  vessel,  and  posi- 
tive circulatory  vessels.  In  the  mollusca  there  is  a  heart  more 
or  less  complicated,  a  double  system  of  arteries  and  veins;  the 
blood  is  white  or  bluish.  Finally  in  the  vertebrata,  besides 
the  arteries,  veins  and  heart,  there  is  a  particular  system  of 
lymphatic  and  chyliferous  vessels  which  convey  the  nourish- 
ing fluid  from  the  intestines  into  the  veins. 

The  simplest  heart  is  composed  at  least  of  a  ventricle  which 
propels  the  blood  into  the  arteries,  and  is  often  accompanied 
with  an  auricle  or  venous  sinus  at  their  entrance  into  the  heart; 
it  is  called  aortic  when  it  sends  the  blood  to  the  whole  body, 
and  pulmonary  when  it  sends  it  to  the  respiratory  organs;  it 
is  double  when  there  are  two  ventricles,  which,  however,  may 
be  separated  or  united.  The  heart  is  simple  without  auricle 
and  pulmonary,  in  all  the  articulated  animals  which  are  pro- 
vided with  one.  The  same  is  the  case  in  fishes,  with  the  ex- 
ception of  there  being  an  auricle.  The  heart  is  simple  but 
aortic  in  most  mollusca;  it  is  triple  in  the  cephalopodous  mol- 
lusca, in  which  there  are  two  pulmonary  ventricles  and  one 
aortic,  separated  and  without  auricles.  In  all  reptiles  there  is 
one  ventricle  only,  more  or  less  divided  by  a  partition,  and 


OP   ANIMALS.  37 

which  sends  the  blood  into  one  single  trunk,  both  aortic  and 
pulmonary;  the  greater  number  have  two  auricles,  the  batra- 
chia  have  only  one.  Finally  the  heart  is  double  in  birds  and 
the  mammalia,  they  have  two  auricles  and  two  ventricles  in 
contact,  one  aortic  and  the  other  pulmonary. 

§  21.  In  order  that  the  nutritive  fluid  may  be  fitted  for  its 
function,  it  must  be  submitted  to  the  action  of  the  atmosphere 
in  which  the  animal  lives.  In  those  which  have  no  circula- 
tion the  water  acts  on  the  surface  of  the  body;  such  seems  to 
be  the  case  with  the  infusoria,  polypi,  and  acalepha: — the  in- 
testinal worms  also  have  not  the  least  appearance  of  respiratory 
organs.  In  another  degree  of  organization,  air  or  water  pene- 
trates into  every  part  of  the  body  by  elastic  canals  called  tra- 
cheae, and  which  are  lined  by  a  prolongation  of  the  skin.  The 
echinodermata  have  aquiferous  tracheae;  in  insects  there  are  two 
longitudinal  tracheae  extending  throughout  the  body,  having 
at  intervals  common  centres  from  which  arise  many  branches, 
and  which  correspond  to  stigmata,  or  external  openings  for 
the  entrance  of  air.  In  animals  that  have  acirculation,  part 
of  the  vessels  carries  the  blood  into  an  organ  in  which  they 
are  subdivided  over  an  extensive  surface  of  the  external  or  in- 
ternal skin.  This  surface  is  salient  and  is  called  branchiae  when 
the  ambient  element  is  water,  and  lungs,  and  hollow,  when  that 
element  is  air.  In  order  to  carry  on  the  branchial  or  pulmo- 
nary respiration,  there  are  generally  organs  for  motion,  to  put 
the  ambient  fluid  in  contact  with  the  organ.  In  the  arachnides, 
we  find  the  transition  of  disseminated  respiration,  which  yet 
exists  in  the  tracheariae,  to  the  local  respiration,  which  occurs 
in  pulmonary  sacs.  In  the  Crustacea  generally,  the  respirato- 
ry organs  are  projecting  branchiae  variously  configured.  The 
same  is  the  case  with  most  of  the  annelides.  In  the  mollusca, 
generally,  we  find  a  very  great  variety  in  the  organs  of  respi- 
ration. Some  breathe  the  air  itself,  and  have  a  pulmonary 
cavity;  these  are  the  gasteropodia  with  lungs;  others  have  pro- 
jecting branchiae  variously  configured;  others  again  have  their 
branchiae  in  a  cavity  into  which  the  water  is  drawn.  In  fishes, 
respiration  is  branchial;  but  it  is  pulmonary  in  the  other  ver- 
tebrated  animals. 


38  INTRODUCTION. 

Respiration  is  partial,  and  circulation  simple  in  reptiles,  in 
which  there  is  only  one  ventricle  and  one  aorta,  of  which  the 
pulmonary  artery  is  a  branch.  In  all  other  animals  which 
have  a  local  respiration  and  a  circulation,  this  latter  is  double, 
and  respiration  complete;  i.  e.  at  every  circuit  of  the  blood, 
the  whole  liquid  passes  through  the  respiratory  organs.  In 
the  articulated  animals  and  mollusca,  the  circle  is  simple;  in 
the  former  the  blood  goes  from  the  heart  to  the  whole  body, 
and  passes  entirely  through  the  branchiae;  the  same  is  the 
case  in  fishes;  in  the  mollusca,  it  goes  from  the  heart  to  the 
branchiae,  passing  first  through  the  whole  body.  In  birds  and 
the  mammalia,  the  two  hearts  being  joined,  the  circle  is  dou- 
ble, or  rather,  the  circuit  is  crossed,  and  ma}r  be  represented 
by  the  figure  8,  at  the  centre  of  which  is  the  heart. 

§  22.  The  nutritive  fluid  must  not  only  be  submitted  to 
the  action  of  the  atmosphere,  but  must  also  be  freed  by  the 
secretions,  from  superfluous  matters.  In  animals  which  have 
an  internal  cavity,  and  consequently  two  surfaces,  these  two 
surfaces,  in  all  their  extent,  serve  for  the  purpose  of  excretion 
as  well  as  of  absorption.  The  internal  and  external  skin  pre- 
sent also  small  cavities  or  particular  depressions  from  which 
the  liquid  issues.  Finally,  even  in  the  animals  in  which  there 
is  no  circulation,  if  some  particular  liquid  is  to  be  produced, 
the  cavities  or  depressions  either  internal  or  external,  of  the 
skin,  are  prolonged  and  ramified  into  the  body  in  the  form  of 
vessels  or  excretory  canals,  and  take  up  from  the  nutritive 
fluid,  the  elements  proper  for  the  composition  of  this  liquid. 
In  the  same  manner,  in  the  animals  which  have  a  circulation, 
the  vessels  sometimes  spread  simply  over  large  surfaces,  and 
permit  the  secreted  fluid  to  escape  by  perspiration;  at  others  it 
is  from  the  bottom  of  small  cavities  or  follicles  formed  either  in 
the  internal  or  external  skin  that  the  liquid  oozes;  in  other  parts, 
the  arteries,  at  the  point  where  the  arteries  change  into  veins, 
communicate  with  ramified  excretory  canals  which  are  always 
formed  by  the  internal  or  external  skin;  and  from  the  union 
and  combination  of  these  canals  with  the  blood  vessels,  result 
the  glands.  These  last  organs  of  secretion  are  peculiar  to  those 
animals  which  have  a  heart  The  liver,  for  instance,  which  is 


OF   ANIMALS.  39 

the  most  general  of  these  organs,  does  not  yet  exist  in  the 
arachnidestracheariae,  but  under  the  form  of  a  separated  vessel 
as  in  insects;  on  the  contrary,  in  the  arachnides  pulmonariae, 
and  in  the  Crustacea,  we  still  find  the  liver  divided  into  dis- 
tinct lobes,  or  as  in  some,  in  the  form  of  a  hunch  of  grapes. 
The  mollusca  have  a  very  considerable  liver;  most  of  them 
have  salivary  glands,  but  neither  pancreas  nor  kidneys.  Se- 
veral have  secretions  peculiar  to  themselves.  All  the  verte- 
brated  animals  have  glands,  and  in  addition  to  what  the  others 
possess,  they  have  kidneys,  organs  which  have  many  points 
of  relation  with  those  of  generation.  Among  the  liquids 
which  result  from  the  various  secretions,  some  have  their  ap- 
propriate use  in  the  exercise  of  the  functions,  as  saliva,  bile, 
&c.; — others,  such  especially  as  the  urine  are  rejected  as  su- 
perfluous and  hurtful. 

Thus  the  organs  of  the  nutritive  functions  in  their  great  di- 
versity, consist  in  a  permeable  absorbing  substance,  which  as- 
similates and  excretes;  in  one  or  two  surfaces,  the  skin  and 
intestines,  which  foreign  substances  have  to  traverse  from 
without  inwardly,  or  from  within  outwardly  by  absorption, 
or  by  excretion;  in  vessels  which  establish  communications 
between  the  surfaces  of  the  body  and  all  the  parts  of  its  sub- 
stance, and  vice  versa;  in  respiratory  organs,  which  are  a  por- 
tion of  the  surfaces,  where  the  liquid  comes  in  contact  with 
the  atmosphere,  and  in  secretory  organs,  another  part  of  the 
surfaces,  where  a  portion  of  the  liquid  is  rejected. 

§  23.  Generation,  or  the  production  of  a  new  being  simi- 
lar to  the  one  to  which  it  owes  its  origin,  is  the  second  func- 
tion in  point  of  importance,  common  to  all  organized  and  liv- 
ing bodies,  and  presents  also  in  animals  a  great  variety  in  its 
organs  and  phenomena.  This  function  in  its  simplest  state, 
has  no  particular  organ  ;  but  the  whole  body  being  very  sim- 
ple and  homogeneous,  divides  itself  in  several  fragments, 
each  of  which  preserve  the  properties  of  the  whole  mass; 
this  is  called  the  fissiparous  generation,  it  belongs  especially 
to  the  infusorii,  and  exists  accidentally  in  others.  In  some 
animals  of  the  same  class,  we  observe  in  the  substance  of  the 
body  globules  or  corpuscular  substances  which  appear  capa- 


40  INTRODUCTION. 

ble  of  reproduction,  this  is  the  subgemmiparous  generation  or 
the  first  indication  of  a  production  of  buds.  In  a  higher  de- 
gree of  animals,  generation  is  truly  gemmiparous,  a  bud  grows 
on  the  external  surface  of  the  body,  and  afterwards  drops  off 
to  form  a  new  being  distinct  from  its  parent,  or  it  continues 
to  remain  united,  and  forms  a  branch  of  it.  This  kind  of  ge- 
neration belongs  to  the  polypi.-  The  internal  gemmiparous  or 
suboviparous  generation  is  also  to  be  met  with  in  theirs.  Its 
organ  consists  in  cavities  prolonged  in  the  mass  of  the  bod}'', 
and  in  the  interior  of  which  grow  buds  or  ovula,  which  sepa- 
rate spontaneously  and  issue  by  traversing  a  canal  which 
opens  on  the  external  surface.  This  mode  of  generation 
is  also  that  of  the  acalepha,  echinodermata,  and  perhaps  in  the 
cestoid  intestinal  worms.  The  acephala  and  some  mollusca 
gasteropoda  differ  only  from  them  because  they  have  a  true 
ovary.  In  all  those  beings,  there  are  properly  speaking  no 
sexual  organs. 

§  24.  In  all  beings  of  a  higher  organization,  there  are 
genital  organs  for  both  sexes,  the  concurrence  of  which  is  ne- 
cessary to  animate  the  germ.  The  female  organs  consist  in  a 
mass  of  germs  or  an  ovary,  and  in  a  canal  through  which  issue 
the  germs  when  detached;  this  is  called  the  oviduct ;  and  in 
several  species,  in  a  cavity  in  which  they  remain  for  a  longer 
or  shorter  time,  into  which  they  ingraft  themselves,  and  in 
which  they  acquire  a  certain  growth  before  they  are  born,  this 
is  the  uterus,  and  the  orifice  through  which  they  come  into 
the  world,  the  vulva.  The  male  organs  are  composed  of  glands 
called  the  testicles,  which  secrete  the  sperm,  a  fecundating  li- 
quor, and  when  this  is  to  be  introduced  into  the  body  of  the 
female,  the  male  is  provided  with  a  penis.  In  this  kind  of 
organization  the  concurrence  of  the  two  sorts  of  organs  is  ne- 
cessary to  bring  about  generation.  We  find  the  first  rudi- 
ments of  this  organization  in  some  intestinal  worms;  but  these 
animals  being  not  provided  with  a  circulation,  their  ovary  and 
testicles  simply  consist  in  free  or  floating  secretory  vessels. 
The  genital  organs  are  also  of  two  kinds  in  many  of  the  mol- 
lusca, in  the  annelides  and  other  articulated  animals,  and  in 
the  vertebrata.  The  ovaries  and  testicles  are  glandular  masses 


OP   ANIMALS.  41 

only  in  those  animals  which  have  a  circulation.  Among  these, 
some  are  hermaphrodite,  or  are  provided  with  both  male  and 
female  organs;  but  this  hermaphrodite  state  is  incomplete,  or 
rather  insufficient;  for  in  order  to  engender  they  require  a 
reciprocal  copulation  with  another  similar  individual:  such 
is  the  case  with  some  annelides  and  mollusca.  In  a  more  ele- 
vated order  of  beings,  the  genital  organs  are  separated  and 
borne  by  different  individuals,  and  this  constitutes  the  sexes. 
This  occurs  in  some  intestinal  worms,  in  many  mollusca,  in- 
secta,  Crustacea,  arachnida,  and  in  all  the  vertebrate  animals. 

§  25.  In  sexual  generation,  the  germ  is  enclosed  with  nu- 
tritive substances  in  a  membranous  or  more  solid,  and  even 
calcarious  envelope ;  then  it  is  called  an  egg.  Sometimes  the 
egg  contains  nutritive  materials  in  a  sufficient  quantity  to  de- 
velope  completely  the  embryo,  and  receives  through  its  cover- 
ings the  influence  of  atmospheric  air  only,  and  scarcely  that  of 
humidity ;  the  animal  is  then  said  to  be  oviparous,  either  if  the 
egg  be  laid  entire,  and  the  development  of  the  embryo  occur 
after  being  laid,  or  if  the  development  precede  the  laying  of 
the  egg,  and  the  egg  break  at  the  moment  of  its  birth.  In 
oviparous  generation,  the  germ  is  only  separated,  generally, 
after  fecundation;  nevertheless,  in  some  instances  the  germ  is 
separated  before,  and  the  egg  is  fecundated  during  or  even 
after  the  laying.  The  egg  does  not  always  contain  sufficient 
materials  for  the  development  of  the  embryo;  in  that  case  it 
ingrafts  itself  by  its  surface  in  the  uterus,  and  absorbs  therein 
nutritive  substances;  the  young  one  is  born  living  with  the 
remains  of  its  membranous  egg,  but  in  a  state  of  weakness 
which  requires  to  be  nourished  with  an  animal  fluid  that  the 
mother  secretes — the  milk.  The  mammalia  are  alone  in  this 
situation.  Some  young  animals,  on  quitting  the  egg  bear  no 
resemblance  to  their  parent;  they  experience  before  reaching 
their  form  a  change  which  is  called  metamorphosis:  such  are 
the  larva  of  insects,  and  the  tadpole  of  the  batrachia;  the 
others,  on  the  contrary,  are  born  similar  to  their  parents,  or 
at  least  there  are  only  some  slight  differences  of  proportion, 
which  in  time  disappear. 

§  26.     Nutrition  and  generation  are  not  the  only  two  modes 


42  INTRODUCTION. 

of  the  formation  or  production  of  animals;  they  possess  also, 
although  in  a  less  degree  or  less  general  manner  than  vegeta- 
bles, the  faculty  of  reproducing  by  a  kind  of  vegetation,  parts 
which  have  been  cut  off  or  destroyed  ;  but  the  faculty  is  not 
even  in  the  same  degree  in  every  animal:    The  simplest  ani- 
mals in  organization  possess  it  in  the  greatest  perfection.     The 
polypi,  and  especially  the  hydra,  always  reproduce  those  por- 
tions which  have  been  cut  off,  so  that,  individuals  are  multi- 
plied by  the  simpleact  of  division  of  parts.  The  power  of  repro- 
duction of  the  actinia  is  no  less  extensive;  they  reproduce 
parts  which  have  been  taken  away,  and  are  multiplied  by  the 
division.     The  asterias  have  also  a  great  power  of  reproduc- 
tion ;  they  again  produce  the  rays  which  are  destroyed;  even 
when  a  single  ray,  provided  it  be  entire,   can  reproduce  the 
others. — The  faculty  possessed  by  the  toenia  of  reproducing 
the  posterior  rings  of  their  body  is  well  known.     Among  the 
annulosa,   the  nereides  has  also  a  very  great  power  of  repro- 
duction.    Experiments  have  been  performed  on  the  lobster, 
which  went  to  prove  the  power  possessed  by  this  animal  of 
shooting  out  a  new  foot  whenever  it  has  been  injured  by  acci- 
dent.    It  seems  that  the  arachnides  also  have  the  faculty  of  re- 
generating legs  which  they  have  lost.     The  aquatic  salaman- 
ders have  also  an  astonishing  power  of  reproduction;  they 
shoot  out  several  times  in  succession  the  very  same  limb  when 
cut,  and  that  too,  with  its  bones,   muscles,  vessels,  &c.     The 
limbs  and  tails  of  the  tadpole  of  the  frog  is  also  regenerated 
very  much  like  those  of  salamanders.     The  tail  of  the  sauria, 
when  torn  off,  grows  again,  although  sometimes  a  little  differ- 
ent from  the  first  one.     In  warm  blooded  animals  the  power 
of  reproducing  parts  which  had  been  removed  by  excision, 
is  almost  confined  to  epidermic  or  horny  parts.     As  to  the 
other  parts,  this  power  does  not  extend  beyond  the  healing  of 
wounds,  and  the  production  of  a  cicatrice  analogous  to  the  skin, 
when  this  latter  is  cut  off  or  destroyed. 

The  organs  and  functions  belonging  to  animals,  present,  like 
the  preceding,  many  degrees  of  complication  or  varieties  in 
the  beings  which  compose  the  animal  kingdom. 

§  27.  In  the  simplest  animals  the  body  being,  or  appearing 


OF    ANIMALS.  43 

to  be  homogeneous,  we  perceive  no  particular  organ  for  mo- 
tion, and  nevertheless  these  infusory  animalcule  move  about 
with  great  rapidity.  There  are  other  animals  a  little  more  com- 
plicated, which  are  yet  unprovided  with  any  kind  of  distinct 
muscular  organ:  such  as  the  rotiferae,  which  have  a  particular 
rotatory  organ,  or  like  the  polypi,  which  have  around  their 
mouth  tentacula,  the  movement  of  which  agitates  the  water, 
and  with  which  they  attract  and  seize  nutritious  substances, 
and  some  of  which  possess,  besides,  movements  performed  by 
the  whole  body.  The  proper  organ  of  visible  motion,  the 
muscular  fibre,  exists  in  the  acalepha,  and  in  the  echinoder- 
mata,  the  muscular  system  of  which  is  supported  by  a  well  or- 
ganized skin,  and  in  all  the  more  elevated  animals  in  which 
the  apparent  movements  either  general  or  partial,  are  pro- 
duced by  the  action  of  these  organs.  The  muscular  fibres,  in 
all  animals,  which  have  any*,  supply  the  external  and  internal 
skin:  they  also  form  the  heart  of  such  animals  as  possess  one. 
Among  animals,  some  have  the  skin  as  soft  as  jhe  other  parts 
of  the  body;  in  a  great  many,  it  contains  within  its  thickness 
indurations,  either  calcarious,  or  horny,  which  shield  the  ani- 
mal from  external  injuries,  and  which  being  moveable  on  each 
other,  transmit  to  the  parts  they  support,  the  motion  that  they 
have  previously  received  from  the  muscles. — In  the  verte- 
brate animals,  this  latter  office  is  fulfilled  by  moveable,  articu- 
lated, internal  bones,  and  which  for  this  reason  are  provided 
with  a  great  mass  of  muscles  which  is  either  wanting  in  the 
invertebrata,  or  is  attached  on  their  cataphracted  or  indurated 
skin. 

§  28.  In  the  simplest  animals,  the  organs  of  the  sensations 
have  no  distinct  existence.  The  whole  body  seems  to  receive 
impressions  as  it  executes  movements.  In  those  which  have 
an  external  and  internal  skin  different  from  the  remaining 
parts  of  the  body,  and  all  from  the  polypi  upwards,  have  this 
arrangement,  the  skin,  besides  the  function  of  absorbing  nu- 
tritious substances,  receives  the  impression  of  external  bodies. 
In  those  animals  which  have  a  very  soft  skin  and  but  little  dif- 
ferent from  the  other  parts,  it  is  every  way  equally  sensitive. 
But  the  part  of  the  skin  which  is  moistened  in  various  animals 


44  INTRODUCTION. 

with  mucus  or  with  a  sebaceous  matter,  is  in  many,  provided 
with  an  epidemics,  hairs,  horny  scales,  or  a  calcareous  crust, 
and  becomes  also  an  organ  of  defence  and  support.  In  this 
case,  some  parts  are  not  covered  with  these  envelopes,  are 
very  moveabie,and  constitute  particular  organs  of  touch;  such 
are  the  tentacula  of  sea-urchins,  those  of  some  fish,  those 
of  mollusca;  the  antennae  of  insects  and  Crustacea,  &c. 

The  organ  of  taste  is  not  to  be  met  with,  distinctly,  in  all 
animals  which  digest,  and  )~et  it  seems  requisite  that  this  sen- 
sation should  exist  in  all.  In  the  radiated  animals,  nothing  is 
to  be  perceived,  at  the  entrance  of  the  alimentary  canal,  which 
seems  to  be  that  organ.  The  same  is  the  case  with  respect  to 
the  mollusca  and  articulated  animals.  In  some  insects,  how- 
ever, this  faculty  is  supposed  to  exist  in  the  extremity  of  the 
proboscis  or  palpi;  finally,  all  the  vertebrata  are  far  from  hav- 
ing a  tongue  organized  in  a  manner  to  enable  them  to  taste. 

The  organ  of  smell  seems  to  be  wanting  in  a  great  number 
of  animals;  insects,  however,  Crustacea,  and  arachnides  are  sen- 
sible to  odours,  but  the  precise  seat  of  their  sensation  is  en- 
tirely unknown.  The  same  may  be  said  with  respect  to  the 
mollusca.  Even  in  the  vertebrata  the  nasal  fossae  do  not  tra- 
verse the  face  in  all  the  classes. 

The  organ  of  hearing  or  the  ear  is  not  found  in  the  lower 
classes  of  animals,  and  sound  seems  to  be  only  perceived  as  a 
tactile  impression.  Among  articulated  animals  the  crab  is  the 
only  one  in  which  we  observe  an  ear,  though  they  all  hear 
very  well.  The  ear  in  the  crab  consist  of  a  bag  filled  with  a 
gelatinous  lymph,  which  receives  a  separate  nerve.  In  the 
same  manner,  the  mollusca  and  cephalopoda  have  this  organ, 
which  exists  in  the  vertebrata,  and  which  presents  a  great  va- 
riety. 

Light  has  also  an  action  on  the  skin  of  all  animals,  and  on 
every  part  exposed  to  its  influence;  but  the  faculty  of  sight  is 
possessed  only  by  those  who  have  its  organ,  the  eye.  The 
radiated  animals  have  no  eyes.  A  portion  of  the  annelides  are 
deprived  of  it;  in  the  others  we  only  meet  with  the  rudiments; 
it  is  a  mere  black  spot.  The  articulata  with  feet,  viz:  the  crus- 
tacea,  arachnides  and  insecta,  have  all  eyes  which  may  be  of  two 


OP    ANIMALS.  45 

kinds,  more  or  less  numerous,  and  always  symmetrical;  viz. 
simple  eyes,  the  cornea  of  which  present  only  one  facet,  the 
iris  only  one  opening,  and  the  optic  nerve  a  single  filament, 
and  compound  eyes,  or  with  man}*  facets  with  as  many  pupils 
and  with  as  many  filaments  of  the  optic  nerves.  Sometimes 
the  eyes  are  pediculated  or  placed  on  articulated  appendages. 
The  acephalous  mollusca  are  deprived  of  eyes;  most  gastero- 
poda have  them,  but  small  and  rudimental,  placed  either  on 
the  head  or  the  posterior  tentacula.  The  cephalopoda  have 
two  large  eyes  covered  with  a  transparent  skin.'  In  the  ver- 
tebrated  animals,  the  eyes  are  wanting  in  a  very  small  num- 
ber of  species. 

§  29.  The  nervous  system  is  unknown  and  seems  not  to 
exist  in  the  infusorii.  The  first  rudiments  of  it  are  to  be  ob- 
served in  the  radiated  animals.  The  Hydra,  among  polypi, 
possess  microscopic  globules  the  nature  of  which  is  uncer- 
tain. But  in  the  sea-star  and  in  the  Holothuria  there  are  gan- 
glia arranged  in  a  circular  form  around  the  mouth,  communi- 
cating with  each  other  by  soft  filaments,  distributing  others  in 
a  radiating  manner  to  the  different  parts  of  the  body,  where 
some  are  conveyed  to  the  external,  and  others  to  the  internal 
skin.  In  some  intestinal  worms  we  observe  a  nervous  ring 
around  the  mouth,  whence  arise  two  cords  which  extend  the 
whole  length  of  the  body.  In  the  articulated  animals  the  ner- 
vous system  presents  a  tolerably  general  character.  There  is 
a  little  enlargement  placed  on  the  sesopbagus  called  brain,  fur- 
nishing nerves  to  the  parts  which  are  connected  with  the  head. 
Two  cords,  which  encircle  the  aesophagus  like  a  necklace,  ex- 
tend under  the  intestinal  canal,  and  unite  at  intervals,  forming 
as  many  double  ganglia  or  knots  as  there  are  rings  in  the  body; 
thence  arise  the  nervas  of  the  trunk  and  those  of  the  extremi- 
ties when  any  exist.  The  arrangement  is  nearly  the  same  in 
the  cirrhipoda.  In  the  mollusca  there  is  a  greater  variety  than 
among  the  articulated  animals.  These  means  of  communica- 
tion, however,  are  ganglia  united  by  cords,  and  conveying 
filaments  to  the  different  external  and  internal  parts.  In  the 
acephala  there  is  above  the  mouth  a  principal  ganglion,  im- 
properly called  brain,  and  another  at  the  opposite  extremity 


46  INTRODUCTION. 

of  the  body;  behincl  the  intestines,  txvo  nervous  branches  es- 
tablish a  communication  with  the  various  ganglia,  and  em- 
brace in  their  lateral  extension,  the  viscera;  other  filaments 
are  distributed  to  the  different  parts  of  the  body.  In  the  mol- 
lusca  provided  with  a  head,  there  is  a  nervous  enlargement  or 
a  principal  medullary  mass  called  brain,  situated  across  and 
over  the  aesophagus  which  it  envelops  with  a  nervous  ring, 
which  terminates  underneath  in  another  but  larger  ganglion: 
these  enlargements  send  filaments  to  the  head  and  to  the  va- 
rious parts  of  the  viscera.  In  some  of  them,  there  are  besides 
other  small  ganglia.  The  cephalopoda  alone  have  their  brain 
enveloped  in  a  kind  of  cartilaginous  cranium. 

The  general  character  of  the  nervous  system  of  the  inver- 
tebrate animals,  particularly  consists  in  the  dissemination  of 
the  nervous  centres,  and  in  the  circumstance  that  the  parts 
either  external  or  internal,  or  those  which  belong  to  the  vege- 
tative functions,  or  those  which  belong  to  the  animal  func- 
tions, receive  their  nervous  filaments  from  the  same  centres. 
We  shall  see,  on  the  contrary,  that  in  the  vertebrata  the  ner- 
vous system  is  differently  disposed,  and  in  a  manner  which 
entirely  distinguish  them  from  other  animals. 

§  30.  Nervous  action  or  innervation,  presents  in  animals 
varieties  corresponding  to  those  which  are  observed  in  the 
disposition  of  the  nervous  organs.  In1  those  animals  which 
have  no  nervous  system,  and  in  those  in  which  this  system  has 
no  centre,  (the  radiated  animals,)  impressions  are  immediate- 
ly followed  by  movements;  a  part  or  an  animal  is  called  irri- 
table whose  movements  are  produced  by  impressions.  In  the 
radiated  animals  the  mouth  or  the  orifice  through  which  they 
take  their  nourishment  is  the  most  irritable  part;  it  is  also  at 
this  place  the  nervous  system  begins  to  appear  in  animals  of 
this  class  provided  with  it.  All  other  animals  have  also  irri- 
table parts.  In  the  mollusca  and  in  the  insecta  in  which  the 
divers  ganglia  of  the  nervous  system  are  connected  with  each 
other  by  nervous  cords,  in  such  a  manner  as  to  form  a  centre, 
and  in  which  there  are  organs  of  a  special  sensation,  the  im- 
pressions received  by  the  senses  produce  sensations,  and  the 
movements  are  caused  by  volition.  The  internal  movements, 


OF   ANIMALS.  47 

however,  are  produced  by  irritation,  but  irritability  in  these 
animals  is  dependent  upon  the  nervous  system.  We  also  ob- 
serve in  them,  and  especially  in  insects,  a  faculty  called  in- 
stinct^ and  which,  like  an  irresistible  impulse,  causes  them  to 
produce,  without  being  taught  and  without  imitation,  very 
complicated  actions,  that  are  necessary  to  their  preservation 
and  to  that  of  their  species.  The  vertebrated  animals  besides 
irritability,  sensibility,  voluntary  movements  and  instinct, 
have  cerebral  functions  which,  to  a  certain  degree,  resembles 
intellect. 

§  31.  The  varieties  or  the  degrees  of  complications  which 
exist  in  each  apparatus  or  function,  are  combined  in  various 
modes,  which  constitutes  the  varieties  of  the  general  orga- 
nization. The  combination  or  the  coexistence  of  the  vari- 
ous apparatuses  of  organs  is  determined;  a  certain  state  of 
the  nutritive  or  genital  organs  requiring,  for  the  support  of 
life,  some  corresponding  state  of  the  organs  of  motions,  of 
sensibility,  &c.  According  to  a  well  defined  distinction  of  or- 
ganization, animals  are  divided  into  vertebrate  and  inverte- 
brate. Man  belongs  to  the  former  of  these  divisions. 

§  32.  Although  the  invertebrata  differ  greatly  from  man, 
their  study  is  nevertheless  of  great  utility  to  the  anatomist  and 
physiologist ;  we  observe  in  them  organization  and  life  in 
their  greatest  simplicity?  and  under  a  multitude  of  varieties. 
They  differ  so  much  with  each  other,  that  they  have  no  com- 
mon and  positive  character.  According  to  their  organization, 
they  are  divided  into  three  great  sections  which  differ  from 
each  other  as  much  as  they  are  unlike  the  vertebra:  these  are 
the  radiated  animals,  the  mollusca,  and  the  articulata;  and  we 
find  even  besides  these  three  divisions,  a  class  of  very  ques- 
tionable beings  that  zoologists  describe  under  the  name  of  in- 
fusorii,  and  which  botanists  claim  as  belonging  to  the  con- 
ferva. 

§  33.  These  dubious  and  microscopical  animals,  have  a  very 
simple  organization,  different  forms,  and  sometimes  changea- 
ble; they  are  homogeneous,  transparentand  diffluent;  they  have 
no  cavity,  no  distinct  organ;  they  move,  however,  in  the  water 
8 


48  INTKODUCTION. 

which  contains  them,  are  nourished  by  imbibition,  and  mul- 
tiply by  spontaneous  division. 

§  34.  The  radiated  animals  constitute  a  particular  type, 
the  essential  character  of  which  consists  in  the  form,  which 
is,  a  centre  around  which  the  other  parts  are  arranged  like  the 
spokes  of  a  wheel.  Their  structure,  rather  simple,  presents 
several  varieties  from  the  simplest  among  them,  the  hydra  or 
polypus  with  arms,  to  the  asterias  or  sea-star.  They  all  in- 
habit the  water. 

§  35.  The  polypi  form  an  extremely  numerous  class  of  ra- 
diated animals.  They  are  generally  elongated,  having  one 
single  orifice  or  mouth  furnished  with  radiating  appendages; 
they  have  an  alimentary  cavity,  digest  very  quickly,  and  ab- 
sorb by  imbibition,  produce  buds  which  sometimes  remain  ad- 
herent and  form  complicated  phytoid  animals,  and  at  others 
separate.  The  external  and  internal  surfaces  are  alike;  the 
intermediate  substances  are  homogeneous  and  gelatinous;  no 
peculiar  organ  is  observable,  except  microscopical  globules, 
and  they  possess  in  a  high  degree  the  power  of  reproduc- 
tion, for  when  divided,  each  part  becomes  an  individual. 
Light,  noise,  and  other  exterior  causes,  produce  on  them  im- 
pressions followed  by  motions.  Some  are  fixed  to  the  ground, 
others  are  free.  The  simplest  of  all  are  those  which  are  neck- 
ed, as  the  hydra,  &c.;  they  have  a  simple  alimentary  sac, 
and  multiply  by  external  buds.  Others  again  which  are  unit- 
ed, excrete  from  their  external  surface  a  horny  or  calcareous 
substance  called  polypier.*  Finally,  in  others,  which  are 
complicated  animals,  the  common  body  envelops  a  secreted 
substance,  the  consistence  of  which  varies  from  that  of  jelly 
to  that  of  stone. 

§  36.  The  acephalous  animals  or  sea-nettles  (medusae,) 
have  a  still  more  circular  or  radiated  form ;  they  are  compared 

*  Under  this  appellation  are  grouped  the  calcareous  substances  8tc.  known 
under  the  name  of  madrepore,  coral,  &c.  which  are  the  excretions  of  the  po- 
lypi here  alluded  to  and  serving  them  for  habitation.  These  calcareous 
excretions  are  comprehended  by  the  French  under  the  general  designation  of 
polypier,  for  which  there  is  no  adequate  term  in  the  English  language. 

TRASS. 


OP  ANIMALS.  49 

to  rosaceous  or  radiated  flowers.  Their  structure  is  various, 
for  some  are  as  simple  as  the  most  simple  polypus,  and  others 
are  much  more  complicated ;  the  mouth  is  central,  furnished 
with  tentacula,  leading  into  a  stomach,  often  ramified,  but 
which  has  no  other  issue.  There  are  for  the  purposes  of  ge- 
neration, a  number  of  oviform  internal  Tbuds  in  particular 
cavities. 

§  37.  The  echinodermata  are  the  radiated  animals,  the  or- 
ganization of  which  is  the  most  complicate:  the  class  contains 
the  stellated,  the  spheroidal  and  the  cylindric  forms.  They 
have  an  internal  cavity  in  which  distinct  viscera  float;  their 
intestine  has  vascular  like  prolongations  ramified  through  the 
body.  Some  have  a  distinct  anus;  the  organs  of  respiration 
are  ramified  aquiferous  canals  ;  the  organs  of  generation  are 
oviform  masses  of  internal  buds,  which  terminate  either  at 
the  mouth  or  at  the  anus  ;  they  have  muscles,  and  in  the 
greater  number  there  are  particular  organs  of  locomotion, 
consisting  in  numerous  tentacula  terminating  in  the  form  of  a 
cupping  glass,  called  feet ;  the  skin  is  well  organized,  and 
often  solid ;  some  have  even  nervous  filaments. 

§  38.  The  articulated  animals  constitute  a  division  of  the 
animal  kingdom  in  which  the  body  is  symmetrical,  divided 
externally  in  a  certain  number  of  rings  or  moveable  segments, 
and  formed  by  the  skin,  more  or  less  tough  and  sometimes 
hard,  except  between  the  intervals  of  the  rings  in  which  it  al- 
ways retains  its  softness  and  flexibility.  Their  muscles  are 
connected  with  the,  inside  of  the  skin;  their  nerves  are  cords 
with  enlargements  at  intervals,  situated  beneath  the  intestinal 
canal.  This  type  however  comprehends  extremely  varied  or- 
ganizations. Some  are  vermiform,  without  head  and  articu- 
lated feet,  and  can  only  creep:  these  are  the  worms  and  the 
annelides. 

§  39.  The  intestinal  worms,  or  the  helminthia,  which  bear 
some  general  resemblance  to  the  radiata,  have  the  body  com- 
monly elongated,  cylindrical  or  depressed,  naked  and  soft;  they 
have  no  organ  either  of  respiration  or  circulation.  Their  genera- 
tion is  internal,  gemmiparous,  and  sexual,  oviparous;  they  inha- 
bit the  bodies  of  other  animals,  and  present  otherwise  very  dif- 


50  INTRODUCTION. 

ferent  degrees  of  organization.     The  simplest  of  all,  the  cestoid 
species,  the  ligula,  resemble  a  long  striated  ribbon,  marked  with 
a  longitudinal  line.     No  external  organ,  not  even  suckers,  are 
perceived  on  them,  and  nothing  internally,  but  oviform  corpus- 
cules  in  the  mass  of  the  body.    Others  again,  whose  forms  are 
much  varied,  such  as  the  trematodes  and  tenioides,  have  only  on 
the  exterior  a  greater  or  smaller  number  of  suckers,  sometimes 
ramified  in  the  body,  which  present  other  canals,  either  gem- 
miferous or  ovariferous.     The  acanthocephali  echinorhynchi 
have  a  proboscis  armed  with  hooks,  furnished  with  muscles; 
they  have  two  little  coeca,  and  also  either  distinct  oviducts,  or 
spermatic  bladders,  according  to  the  sexes,  which  are  sepa- 
rated.    The  nematoides,  as  the  ascarides,  &c.;  are  still  more 
complexly  organized;  they  have  a  mouth  and  anus,  and  an  in- 
testinal canal  floating  in  a  distinct  abdominal  cavity;  their  ex- 
ternal skin  is  furnished  with  muscular  fibres,  in  general,  trans- 
versely striated.     They  have  distinct  genital  organs  consisting 
of  long  canals.     The  sexes  are  separated.    They  have  a  ner- 
vous ring  which  surrounds  the  mouth,  and  two  long  cords,  one 
dorsal,  the  other  ventral;  they  have  also  two  spongy,  lateral 
vessels. 

§  40.  The  annelides  or  red  blooded  worms  are  vermiform 
animals,  whose  elongated  bodies  are  divided  into  numerous 
rings,  the  first  of  which,  called  the  head,  differs  but  little  from 
the  rest;  the  mouth  is  either  a  mere  tube  or  jaws.  There  is  an 
intestine  longer  or  shorter,  which  traverses  the  body;  there  is  a 
double  system  of  arteries  and  veins,  without  any  well  defined 
heart;  the  blood  is  red,  the  respiration  branchial.  They  are 
hermaphrodites,  with  a  mutual  copulation,  they  have  muscles, 
and  the  greater  number,  stiff  bristles  serving  for  feet;  the  head  is 
furnished  with  tentacula,  and  some  of  them  with  black  points 
that  are  considered  as  eyes;  the  nervous  system  consists  in  a 
knotty  cord. 

§  41.  The  other  articulated  animals,  are  all  provided  with 
a  head,  and  have  all  eyes,  either  simple  or  compound;  their 
very  complex  mouths,  greatly  resemble  one  another,  and  pre- 
sent two  modifications:  in  the  first,  for  the  purpose  of  grind- 
ing, there  are  several  pairs  of  lateral  jaws,  the  anterior  of  which 


OP  ANIMALS.  51 

are  called  mandibles  and  often  palpi,  articulated  filaments, 
which  appear  to  serve  in  recognizing  their  food:  in  the  second, 
there  is  a  proboscis  for  suction.  The  organs  of  digestion  are 
complicated  and  various.  They  enjoy  the  sense  of  smell,  but 
its  seat  is  not  well  determined.  They  have  all  an  abdomen, 
and  a  thorax  which  supports  six  articulated  feet,  at  least.  Their 
skin  is  encrusted  and  solid,each  articulation  of  the  feet  is  tubular 
and  contains  the  muscles  of  the  succeeding  one.  All  the  ar- 
ticulations <K  the  feet  are  by  gynglymus;  generation  is  sexual 
and  oviparous.  This  section  contains  three  great  classes,  that 
of  insects,  the  arachnides,  and  the  Crustacea. 

§  42.  Insects,  or  the  hexapoda,  have  the  body  composed  of 
segments  or  numerous  rings,  and  divided  into  three  principal 
parts,  six  articulated  feet,  a  distinct  head  furnished  with  eyes, 
and  two  antennae,  a  thorax  which  supports  the  feet  and  wings, 
when  there  are  any,  and  an  abdomen  which  contains  the  prin- 
cipal viscera.  The  mouth  is  very  complex,  in  the  grinders, 
there  are  lateral  jaws,  in  the  suckers  there  is  a  proboscis.  The 
intestinal  canal  more  or  less  long,  enlarged,  contracted,  &c,, 
terminates  by  an  anus.  There  is  a  vestige  of  a  heart  in  a  vessel 
attached  along  the  back,  divided  into  segments  by  strangula- 
tions, and  which  experiences  alternate  contractions.  The  fluid 
it  contains  is  white,  and  appears  to  penetrate  it,  like  the  rest 
of  the  body,  by  imbibition.  Respiration  is  effected  by  means 
of  ramified  tracheae  united  in  two  principal  trunks.  The  se- 
cretory organs  consist  in  long  spongy  vessels  or  canals,  dou- 
bling on  themselves,  running  through  the  mass  of  the  body, 
and  ending  either  in  the  intestine  or  elsewhere,  according  to 
the  uses  of  their  products.  The  sexes  are  separated  most  fre- 
quently, the  genital  organs  terminate  in  the  anus.  These  ani- 
mals copulate  but  once  in  their  life.  The  impregnated  female 
deposits  her  eggs  in  a  suitable  spot,  and  the  eggs  produce  ver- 
miform animals  called  larvae,  which  changes  into  a  chrysalis, 
a  state  of  apparent  death;  and  from  which  emerges  the  perfect 
insect  that  soon  propagates  its  species  and  dies.  This  consi- 
derable change  of  external  form,  accompanied  by  others  more 
or  less  great  in  the  structure,  is  called  a  metamorphosis;  all  in- 
sects, the  thysanouraand  the  parasiticaexcepted,  which  by  their 


52  INTRODUCTION. 

resemblance  to  mites,  approximate  to  the  arachnides — undergo 
it;  some  of  them  however  do  not  suffer  this  change  in  all  its 
extent,  and  it  is  then  called  imperfect.  The  organs  of  motion 
are  the  muscles  and  the  skin,  hardened  by  a  horny  substance 
contained  within  its  thickness;  there  are  six  articulated  feet, 
and  generally  four  wings,  some  have  only  two,  while  a  very 
small  number  are  apterous.  Their  motions  are  greatly  varied, 
and  consist  in  the  walk,  running,  jumping  and  flight.  The  or- 
gans of  the  sensations  are  compound  eyes,  and  in  many  simple 
ones,  generally  three  in  number;  antennae  and  palpi.  They  enjoy 
both  hearing  and  smell,  but  their  organs  are  unknown.  The 
disposition  of  the  nervous  system  is  indicated  in  §  28,  and  ter- 
minates anteriorly  by  a  little  enlargement  or  brain,  situated 
on  the  oesophagus,  and  is  distributed  to  the  eyes  and  other 
parts  of  the  head. 

§  43.  The  arachnides  or  octopoda,  whose  head,  deprived 
of  antennae,  confounds  itself  with  the  thorax,  have  eight  feet 
and  no  wings.  The  alimentary  canal  begins  in  the  one  by  a 
mouth  with  two  lateral  mandibles,  in  the  other  by  a  mouth 
fitted  for  suction  or  by  a  proboscis.  The  greater  number  have 
palpi,  are  subject  to  moults  or  a  changing  of  skin,  and  not  to  a 
metamorphosis.  The  sexes  are  separated,  generation  is  ovi- 
parous, and  they  have  generally  visible  eyes,  which  vary  in 
regard  to  number  and  situation. 

They  present  two  degrees  of  organization;  the  first  or  sim- 
plest is  that  of  tracheal  arteries,  where  there  are  no  organs  of 
circulation  more  apparent  than  in  insects;  the  organs  of  respi- 
ration are  distinct  branching  tracheas.  The  most  complex  is 
that  of  the  pulmonary  or  branchial  arteries,  (spiders,  tarantula 
and  scorpions.)  They  have  a  simple  muscular  heart,  dorsal, 
elongated,  cylindrical,  branchial  or  pulmonary,  whence  are  de- 
rived the  vessels  for  the  respiratory  organs,  which  are  pulmo- 
nary sacs,  and  thence  distributed  to  the  whole  body.  There 
is  also  a  liver  composed  of  lobules  or  grains,  collected  in  clus- 
ters. The  sexual  organs  are  double  in  each  sex.  Some  of  them 
copulate  repeatedly  and  live  several  years;  the  scorpions  are 
ovoviviparous. 

§  44.  The  myriapoda  or  centipedes  form  a  little  group  of 
animals,  intermediate  to  the  Crustacea  which  they  resemble  by 


OP   ANIMALS.  53 

their  form,  and  to  insects  which  they  approach  in  structure, 
still  differing  however  from  both.  Their  body  is  elongated, 
and  formed  of  a  generally  considerable  number  of  rings,  each 
having  one  or  two  pairs  of  feet.  The  head  is  furnished  with, 
antennae  and  two  eyes.  Their  jaws  and  mandibles  are  analo- 
gous to  those  of  the  Crustacea.  Their  respiration  is  tracheal. 
On  quitting  the  egg,  the  young  have  six  feet  and  seven  or 
eight  rings,  the  other  rings  and  feet  which  support  them 
being  developed  by  age. 

§  45.  The  crustacea  are  of  all  the  articulata  with  articulated 
feet,  the  most  complex  in  their  organization.  The  head  and  the 
rest  of  the  trunk  are  sometimes  confounded,  and  at  others 
distinct,  they  have  a  tail  more  or  less  elongated,  divided  into 
segments,  and  commonly  four  antennae.  The  greater  part  of 
them  have  the  mouth  fitted  for  grinding  and  for  that  purpose 
are  furnished  with  several  jaws,  at  least  six,  always  lateral. 
There  are  always  at  least  fi-ve  pairs  of  feet  for  motion,  whose 
forms  vary  according  to  the  kind  of  movement  to  be  performed. 
The  number  of  locomotive  feet  is  in  an  inverse  ratio  to  that  of 
the  jaws:  in  fact  the  anterior  feet  approximate  to  the  jaws,  in 
taking  their  form,  and  in  filling  a  part  of  their  functions,  they 
can  even  completely  take  their  place.  For  respiration  they 
have  pyramidal  lamellated  filamentous  and  tufted  branchiae, 
generally  adhering  to  the  base  of  some  of  the  feet,  or 
which  they  even  partly  replace.  Their  circulation  is  double; 
the  blood  that  has  been  submitted  to  the  respiratory  action,  is 
poured  into  a  great  ventral,  aortic  vessel,  which  distributes 
it  to  all  the  body,  whence  it  returns  by  another  great  vessel  or 
even  a  true  dorsal  ventricle,  which  transmits  it  to  the  bran- 
chiae. They  possess  a  liver,  more  or  less  divided,  sometimes 
even  into  distinct  canals,  according  to  the  state  of  the  heart. 
Generation  is  sexual  and  oviparous,  without  a  true  metamor- 
phosis. The  greater  part  carry  their  eggs  with  them,  and 
they  all  inhabit  the  water.  They  present  otherwise  a  great 
variety  of  organization.  The  jaws,  the  feet  and  the  branchiae 
are  so  nearly  allied,  that  these  appendages  have  all  been  con- 
sidered as  being  of  one  kind,  the  first  resulting  from  a  trans- 
formation of  the  last.  The  greater  part  of  them  have  a  shell 


54  INTRODUCTION. 

more  or  less  solid  than  the  rest  of  the  skin,  which  covers  the 
trunk,  and  in  some  even  the  head.  In  several  orders,  the  sto- 
mach, which  is  highly  muscular,  is  provided  with  a  cartilagi- 
nous skeleton  and  with  tubercles  or  teeth.  The  intestinal 
canal  is  commonly  short  and  straight.  The  position  of  the 
genital  organs  varies;  in  some  genera  these  organs  are  double. 
The  eyes  offer  much  variety,  arid  in  a  few  are  wanting;  in 
others  they  are  very  nearly  joined,  and  seemingly  thrown  into 
one;  some  again  have  compound  eyes,  supported  by  amovea- 
ble  pedicle.  Finally,  in  some  of  the  Crustacea  decapoda,  there 
are  distinct  organs  for  hearing. 

§  46.  The  mollusca  form  a  division  of  the  invertebrata,  in 
which  we  generally  find  a  symmetrical  or  binary  form,  but 
no  articulations.  Their  stomachs  are  simple  or  multiple,  some- 
times furnished  with  hard  parts,  and  their  intestines  variously 
prolonged.  The  greater  part  have  salivary  glands,  all  a  vo- 
lumnious  liver,  and  many  peculiar  secretions.  Their  circula- 
tion is  double,  and  there  is  always  at  least  one  fleshy  ventricle 
which  is  aortic,  and  receives  the  blood  from  the  organs  of  re- 
spiration and  sends  it  back  through  the  arteries  of  the  body. 
In  those  that  have  more  than  one  ventricle,  they  are  not  unit- 
ed in  one  single  mass,  but  form  several  distinct  hearts.  The 
blood  is  bluish.  The  organs  of  respiration  are  sufficiently  di- 
versified to  enable  some  to  respire  air  and  others  water.  Ge- 
neration also  in  them  presents  all  its  varieties;  some  not  hav- 
ing the  sexes  and  producing  living  young  ones  without  copu- 
lation, and  others  being  hermaphrodites  with  a  reciprocal 
copulation,  while  in  a  third  the  sexes  are  separated.  The  eggs 
of  the  latter  are  simply  enveloped  with  a  viscous  matter,  and 
others  again  have  shells  more  or  less  hard.  These  animals 
are  very  prolific  and  very  tenacious  of  life.  Their  muscles 
are  attached  to  the  interior  of  a  soft  and  elastic  skin,  and  their 
movements  are  produced  by  parts  that  have  no  solid  levers. 
They  are  highly  irritable.  Their  naked  skin  is  covered  with 
a  mucous  fluid  that  oozes  from  it.  Almost  the  whole  of  them 
have  a  development  of  the  skin  which  covers  up  the  body 
like  a  mantle,  variously  diversified,  however,  as  to  figure.  This 
mantle  sometimes  remains  soft,  but  most  frequently  it  hap- 


OF    ANIMALS.  55 

pens  that  one  or  more  plates,  now  and  then  horny,  but  oftener 
calcarious,  is  formed  in  its  thickness.  This  substance  is  ordi- 
narily sufficiently  large  to  enable  the  animal  to  cover  itself 
completely  with  it:  this  is  what  we  call  a  shell.  Many  are 
deprived  of  eyes,  some  have  rudimental  ones,  and  those  of 
others  are  highly  developed.  Their  nervous  system  consists 
in  medullary  masses  dispersed  throughout  the  body,  the  chief 
of  which  is  situated  across  the  oesophagus,  which  it  surrounds 
with  a  nervous  circle.  They  have  but  little  instinct,  and  for 
the  most  part  inhabit  the  water.  Besides  this  they  present  se- 
veral differences  of  organization,  some  assume  that  of  the  ra- 
diata,  others  that  of  the  articulata,  and  a  third  by  the  complex 
nature  of  their  organs  approximate  to  the  vertebrata. 

§  47.  The  acephala  without  shells  or  the  tunicata  have  some 
resemblance  to  the  radiated  animals.  Some  are  collected  in  one 
common  body,  like  polypi ;  among  them  some  are  disposed  in  a 
star,  the  anuses  being  in  the  centre,  and  the  mouths  at  the  cir- 
cumference; others  form  a  cylinder  in  which  end  the  anusses, 
the  mouth  opening  externally,  while  others  have  the  viscera 
prolonged  in  a  common  mass,  and  the  radiated  mouth  and  the 
anus  approximated  towards  the  free  extremity  of  the  body. 
A  fourth  kind  only  remains  united,  long  after  birth:  these 
when  they  are  separated  exhibit  the  form  of  a  contractile 
tube  open  at  both  ends,  and  in  the  thickness  of  which  are 
placed  the  viscera.  Finally,  there  are  others  fixed  to  rocks, 
which  resemble  two  tubes,  the  one  enclosed  within  the  other, 
and  between  whose  parieties  they  cause  the  water  to  pass. 
They  all  possess  an  alimentary  canal  with  two  openings,  bran- 
chias,  a  liver,  heart  and  ovaries  or  internal  buds,  which, 
without  copulation,  produce  living  young  ones;  they  have  all 
ganglions  and  nervous  filaments. 

§  48.  The  cirrhopoda  constitute  a  small  group  of  animals, 
intermediate,  between  the  mollusca  and  the  articulata.  Their 
short  body  without  a  head  and  transverse  rings,  is  fur- 
nished with  a  tunick  and  multivalve  shell  which  resemble 
those  of  the  acephala;  the  mouth  has  lateral  jaws,  and  along 
the  belly  there  are  articulated  appendages  with  a  horny  skin, 
disposed  in  pairs,  resembling  the  natatory  feet  of  the  tail  of 


56  INTRODUCTION. 

certain  Crustacea,  called  cirri.  The  stomach  is  provided  with 
little  cells  which  appear  to  perform  the  office  of  a  liver;  the  in- 
testine is  simple;  there  is  a  dorsal  heart  and  lateral  branchiae, 
also  a  double  ovary  or  a  mass  of  internal  buds  and  a  double 
serpentine  canal  for  the  exit  of  the  young.  These  animals  are 
sessile  or  pediculated,  but  always  fixed;  their  nervous  system 
is  a  series  of  ganglions  under  the  belly. 

§  49.  The  acephalous  or  conchyferous  mollusca,  have  the 
body  deprived  of  a  head,  containing  all  the  viscera  and  are 
completely  enveloped,  (like  a  book  by  its  cover)  by  the  man- 
tle doubled  in  two,  and  by  a  calcarious  shell,  generally  bivalve, 
sometimes  multivalve.  The  mouth  is  armed  with  tentacular 
leaflets  concealed  under  the  mantle;  the  anus  is  hidden  in  the 
same  manner;  at  the  other  extremity  there  are  four  very  large 
branchial  leaflets;  the  liver  is  very  voluminous,  embracing  the 
stomach  and  a  part  of  the  intestine  which  greatly  varies.  The 
foot  when  it  exists  is  attached  between  the  four  branchiae,  and 
consists  of  a  fleshy  mass,  which  moves  like  the  tongue  of  the 
mammalia.  The  heart  is  commonly  single,  aortic,  and  placed 
near  the  back.  They  have  one  or  two  muscles  for  closing  the 
shell  and  an  elastic  ligament  which  opens  it;  they  have  also  a 
principal  ganglion  situated  above  the  mouth,  united  to  another 
opposite  by  two  nervous  cords,  and  some  other  nerves  and  gan- 
glions. They  produce  living  young  ones  without  copulation. 

The  branchiopoda,  are  other  acephala,  but  few  in  number, 
which  in  place  of  ieet  have  two  fleshy  arms;  they  appear  to 
have  two  aortic  hearts,  and  a  convoluted  intestine  surrounded 
by  the  liver;  neither  their  generation  nor  their  nervous  system 
is  well  understood. 

§  50  The  gasteropoda  are  cephalous  mollusca  that  generally 
crawl  on  a  fleshy  disk  placed  under  the  belly,  the  back  being 
covered  by  the  mantle  that  varies  in  length  and  figure,  and 
producing  most  commonly  a  univalve  or  multivalve  shell.  In 
this  class  are  to  be  found  some  mollusca  whose  organs  of  res- 
piration and  shell  are  not  symmetrical.  The  head,  placed  for- 
ward and  more  or  less  disengaged  from  under  the  mantle,  pos- 
sesses generally  two,  four,  or  six  tentacula,  situated  above  the 
mouth,  that  perform  the  offices  of  feeling,  seeing,  and  perhaps 


OP  ANIMALS.  57 

smelling.  Most  commonly  there  are  small  punctiform  eyes, 
belonging  to  the  head  or  tentacula;  the  organs  of  digestion  are 
very  varied,  and  there  is  never  more  than  one  heart,  which  is 
aortic:  in  those  that  are  not  symmetrical,  it  is  on  the  left  side 
for  the  greater  number,  and  in  those  that  are,  on  the  right. 
The  respiratory  organs  vary  greatly;  the  greater  portion  of  them 
have  branchia?,  and  some  breathe  air.  The  same  variety  exists 
in  their  modes  of  generation,  being  unisexual  without  copula- 
tion, hermaphrodite  with  a  mutual  coitus,  and  separate  sexes. 

The  pteropoda  consist  of  a  small  group  of  mollusca  between 
the  acephala  and  the  cephala. 

§  51.  The  cephalopoda,  form  a  small  class  that  comprises 
the  inarticulated  animals  the  most  complex  in  their  organiza- 
tion, and  which,  like  the  Crustacea,  among  the  articulata,  ap- 
proximate the  most  to  the  vertebrata. 

They  are  soft  animals,  whose  bodies  are  wrapped  in  a  sac 
formed  by  the  mantle,  the  sides  of  which  project  more  or  less 
in  fins;  through  its  opening  passes  a  round  head,  crowned  with 
feet  or  fleshy  arms,  provided  with  suckers  which  serve  for 
walking,  seizing,  and  swimming.  The  mouth,  situated  be- 
tween the  bases  of  the  feet,  is  armed  with  two  strong  jaws  of 
horn,  resembling  the  beak  of  the  parrot;  there  is  a  tongue  that 
bristles  with  horny  points;  an  oesophagus  swelled  into  a  crop,  a 
second  muscular  stomach  like  a  gizzard,  and  a  third  one  that  is 
membranous;  a  simple  and  short  intestine  ends  in  the  opening 
of  the  sac  before  the  neck.  There  is  a  double  system  of  veins 
and  arteries,  two  branchial  and  one  aortic  ventricle.  The  res- 
piratory organs  are  two  branchiae,  situated  in  the  sac  where  the 
water  for  breathing  comes  and  goes.  The  liver  is  very  large 
and  discharges  the  bile  by  two  ducts  into  the  third  stomach. 
These  animals  have  a  peculiar  black  secretion  produced  by  a 
gland  and  deposited  in  a  reservoir.  The  sexes  are  separate; 
there  is  an  ovary,  two  oviducts,  that  take  and  convey  the  eggs 
thence  out  of  the  body  through  two  large  glands  that  envelop 
them  with  a  viscid  matter,  and  unite  them  in  clusters;  there  is 
a  testicle  and  a  vas  deferens  which  ends  in  a  fleshy  penis  by 
the  side  of  the  anus,  where  terminate  also  a  vesicula  seminalis 
and  a  prostate.  Fecundation  is  performed,  it  is  presumed,  by 


58  INTRODUCTION. 

moistening  the  eggs.  The  eye  is  formed  by  numerous  mem- 
branes, and  covered  by  the  skin,  which  at  this  place  is  trans- 
parent and  which  is  sometimes  so  doubled  as  to  form  folds  or 
eye-lids.  Each  eye  has  a  large  ganglion  giving  rise  to  innu- 
merable nerves.  The  ear  is  a  small  simple  cavity,  sunk  on 
each  side  near  the  brain  without  any  external  canal,  where  a 
small  membranous  bag  is  suspended  that  contains  a  little  stone. 
The  brain  is  contained  in  a  cartilaginous  cavity  which  is  a  ru- 
diment of  a  skull. 

§  52.  Such  is  the  immense  series  of  invertebrate  animals. 
They  constitute,  as  we  have  seen,  three  different  types.  We 
have  also  seen  that  in  each  type  there  is  a  general  resemblance, 
and  also  different  degrees  of  complication  and  perfection  in 
their  organization. 

The  radiata  are  evidently  the  most  simple.  Through  some 
of  their  number  they  approximate  to  the  infusorii.  Even  the 
most  complicated  among  them  have  yet  no  central  organ  of 
circulation,  and  no  predominant  nervous  one:  destitute  of  cen- 
tral organs,  they  have  no  organic  or  vital  unity. 

After  the  radiata  come  the  mollusca  and  the  articulata.  As 
to  the  order  of  organic  superiority  of  these  two  divisions,  it  is 
difficult  to  determine,  for  on  the  one  hand,  if  the  articulata  are 
inferior  to  the  mollusca  as  regards  the  vegetative  organs  and 
functions,  since  many  of  them  are  deprived  of  a  true  circula- 
tion, a  function  existing  in  all  the  mollusca,  on  the  other,  the 
latter  are  inferior  to  the  former  in  the  development  and  ap- 
proximation of  the  nervous  masses,  and  above  all  in  that  in- 
stinct which  is  so  perfect  in  some  of  the  articulata,  as  to  bring 
them  near  to  the  vertebrata. 

OF    VERTEBRATE    ANIMALS. 

§53.  Vertebrate  animals,  or  as  they  are  termed,  the  verte- 
brata, form  a  type  or  mode  of  organization,  to  which  man  and 
those  animals  that  most  resemble  him  belong.  They  resemble 
the  invertebrate  in  the  organs  of  the  vegetative  functions, 
while  they  widely  differ  from  them  in  those  of  the  animal 
functions.  Their  external  conformation,  with  the  exception 


OF  VERTEBRATE  ANIMALS.  59 

of  almost  one  genus,  is  perfectly  symmetrical,  i.  e.  that  their 
organs  of  sensation  and  motion  are  disposed  in  pairs  on 
the  two  sides  of  an  axis  or  of  a  median  line.  They  attain  a 
great  size,  and  it  is  among  them  that  we  find  the  largest  ani- 
mals, which  is  owing  to  the  bones  that  sustain  the  soft  parts. 
Their  bodies  are  composed  of  a  trunk,  and  with  very  few  ex- 
ceptions, of  limbs.  The  trunk  is  upheld  in  its  whole  length 
by  the  spine,  a  column  formed  of  moveable  vertebra  placed 
one  on  another,  at  one  of  whose  extremities  is  the  head;  while 
the  other  is  generally  prolonged  into  a  tail.  This  column, 
partly  solid,  is  pierced  by  a  canal  which  contains  the  spinal 
marrow.  The  head  is  formed  by  the  cranium  which  contains 
the  brain,  and  by  the  face  which  consists  of  the  jaws  and  the 
receptacles  of  the  senses.  The  remainder  of  the  trunk  forms 
one  or  two  great  cavities  which  contain  the  organs  of  the  vege- 
tative functions.  In  most  of  them,  on  the  sides  of  the  column, 
are  bony  arches,  or  ribs,  that  protect  the  great  splanchnic 
cavity,  and  in  the  greater  number,  these  ribs  are  articulated 
in  front  with  the  sternum.  The  limbs  never  exceed  in  num- 
ber two  pairs,  sometimes  one,  sometimes  the  other  of  these 
are  wanting,  occasionally  even  both:  in  other  respects  their 
forms  are  varied  according  to  their  destined  relative  move- 
ments. 

The  vertebratahave  all  two  horizontal  jaws,  most  commonly 
furnished  with  teeth,  hard  bodies  analogous  to  bones  in  their 
chemical  composition,  and  to  horns  in  their  mode  of  forma- 
tion. In  such  as  have  no  teeth  (the  bird  and  tortoise)  we  find 
a  true  horny  matter  in  place  of  them.  In  all  the  vertebrata, 
the  intestinal  canal,  extended  from  the  mouth  to  the  anus,  and 
presenting  several  enlargements,  is  furnished  with  secretory 
glands  viz:  the  salivary  glands,  the  pancreas,  and  the  liver.  All 
have  arteries,  veins,  a  heart  variously  formed  and  chyliferous 
and  lymphatic  vessels.  The  blood  is  red.  In  one  class  only 
(Fish,)  are  there  branchia,  in  the  remainder  the  respiratory 
organ  is  lungs.  Respiration  is  more  or  less  great  or  perfect 
according  to  the  class.  The  organ  for  secreting  bile,  the  liver, 
receives  in  all  the  vertebrata,  blood  brought  from  the  intes- 
tines and  the  spleen  by  the  vena-porta.  They  have  all  kid- 


60  INTRODUCTION. 

neys,  that  secrete  the  urine,  and  the  greater  portion  a  bladder 
or  resevoir  for  this  excrementitious  humour.  The  sexes  are 
always  separate;  the  female  has  one  or  two  ovaries  from 
which  the  eggs  detach  themselves.  The  male  fecundates  them 
with  the  spermatic  fluid,  but  the  mode  of  impregnation  as 
well  as  other  phenomena  of  generation,  greatly  varies. 

The  muscles,  independently  of  those  that  form  the  heart, 
and  those  that  belong  to  the  skin,  the  mucous  membrane  and 
the  senses,  are  very  numerous,  and  are  inserted  into  internal 
bones,  moving  on  each  other.  All  such  as  have  lungs,  have 
also  a  larynx,  although  all  have  not  a  voice.  The  senses  consist 
of  two  eyes,  two  ears,  the  nose,  the  tongue  and  the  skin;  this 
membrane  being  besides  provided  with  several  protecting 
parts,  but  it  is  essentially  the  nervous  system  which  peculiarly 
distinguishes  the  vertebrata.  In  the  invertebrate  animals  the 
same  nervous  enlargements,  more  or  less  separated,  send  fila- 
ments indifferently  to  the  organs  of  the  animal,  as  well  as  the 
vegetative  functions ;  here,  on  the  contrary,  besides  those  gan- 
glions whose  filaments  are  restricted  to  the  organs  of  the  ve- 
getative functions,  there  is  a  particular  centre  with  which  these 
enlargements  communicate, and  from  which  originate  or  where 
terminate  the  nerves  of  the  organs  of  sensation  and  motion. 
This  centre,  perfectly  symmetrical,  consisting  of  a  thick  cord 
enclosed  in  the  spine,  is  extended  into  the  cranium,  where  it 
presents  various  enlargements,  and  is  surmounted  by  two 
complex  nervous  organs,  called  cerebellum  and  cerebrum. 
This  nervous  centre  is  enveloped  by  bones  firmly  united  with 
each  other,  that  defend  it  from  external  injuries.  This  func- 
tion of  the  bones  may  be  regarded  as  one  of  the  most  impor- 
tant they  possess. 

§  54.  Besides  the  kinds  of  humours  and  organs  common  to 
all,  or  at  least  to  the  generality  of  animals,  some  are  found 
among  the  vertebrata,  which  have  no  existence  in  the  others; 
these  are  the  red  blood,  the  lymphatic  and  chyliferous  vessels, 
bones,  ligaments  and  tendons,  and  the  serous  and  synovial 
membranes. 

In  all  the  invertebrata,  the  nutritious  liquid  is  of  one  single 
colour,  and  that  white  or  bluish,  if  we  except  the  annelides 


OP   VERTEBRATE    ANIMALS.  61 

where  it  is  red.  In  the  vertebrata,  on  the  contrary,  the  arte- 
ries, veins  and  heart  contain  red  blood,  a  fluid  composed  of 
colourless  serum,  in  which  corpuscules  float,  formed  of  a  cen- 
tral globule  and  a  coloured  envelope.  Its  composition  is  more 
complicated  than  in  the  invertebrata.  A  whitish  or  slightly  co- 
loured liquid  is  contained  in  the  chyliferous  vessels,  which 
commence  at  the  intestine,  and  in  the  lymphatics  which  arise 
in  every  part  of  the  body,  both  of  which  are  very  analogous 
to  veins,  and  terminate  in  them. 

The  bones  are  hard  parts,  proper  to  the  vertebrata.  They 
are  situated  internally  and  are  of  an  organic  nature,  consisting 
in  a  compact  mass  of  cellular  matter,  containing  a  large  pro- 
portion of  the  phosphate  of  lime.  They  serve  as  envelopes  to 
the  nervous  centres;  they  receive  and  transmit  the  muscular 
motions,  and  finally  serve  as  support  to  all  the  parts,  and 
thereby  determine  the  form  of  the  body.  In  the  invertebrata, 
the  hard  parts,  in  general,  are  exuded  on  to  the  surface  of  the 
skin,  and  consist  of  shells,  crusts,  and  scales  of  carbonate  of 
lime,  or  a  horny  substance.  This  latter  kind  appears  again  in 
the  vertebrata,  where  it  is  variously  disposed,  as  in  horns, 
scales,  feathers  and  hairs,  parts  all  analogous  to  each  other, 
both  in  their  composition  and  mode  of  formation.  We  also 
find  in  the  vertebrata  a  kind  of  organs  which  is  almost  pecu- 
liar to  them;  they  are  the  tendons  which  connect  the  muscles 
with  the  bones,  and  the  ligaments  which  surround  their  articu- 
lations; these  liens  or  ties  are  formed  of  very  highly  condens- 
ed cellular  membrane,  whose  whole  function  consists  in  their 
tenacity. 

The  serous  and  synovial  membranes  are  also  parts  formed  by 
the  condensed  cellular  substance,  disposed  in  the  form  of  sacs 
with  contiguous  parietes  wherever  the  continuity  of  the  parts 
is  interrupted;  in  the  splanchnic  cavities  it  separates  the  viscera 
from  their  walls,  in  the  moveable  articulations  they  contain  a 
liquid  which  lubricates  the  adjoining  extremities  of  the  bones. 

§  55.  But  what  distinguishes  the  vertebrata,  is  not  only  the 
actions  of  the  organs  proper  to  them,  viz:  a  more  concentrat- 
ed nervous  system,  whose  central  parts  are  more  voluminous, 
whence  results  an  appearance  of  intelligence  which  distin- 


62  INTRODUCTION. 

guishes  itself  from  instinct,  a  certain  capability  of  instruction, 
&c. ;  it  is  not  only  the  influence  these  organs  hold  over  the 
others,  in  order  to  direct  their  action,  but  it  is,  above  all,  the 
concentration  of  life  in  the  central  or  predominant  organs — 
in  the  heart,  in  the  nervous  centre,  and  in  the  action  of  these 
parts  on  each  other.  Even  in  this  point  of  view,  however, 
there  is  a  great  difference  among  the  vertebrata. 

§  56.  The  vertebrate  animals  which  are  so  much  alike  in 
most  of  their  characters,  present,  in  fact,  a  very  considerable 
difference.  The  similitude  is  particularly  strong  in  the  cen- 
tral part  of  the  nervous  system,  and  in  its  envelope,  that  is  to 
say,  in  the  spinal  marrow,  and  spine;  and  their  differences  in  the 
extremities  and  at  the  surface,  as  in  the  brain,  the  cranium,  the 
organs  of  sense,  the  face,  the  organs  of  motion,  themembers, 
and  skin.  In  the  same  way,  among  the  organs  of  the  vegetative 
functions,  the  heart  presents  many  differences,  but  they  are 
particularly  great  in  the  organs  and  phenomena  of  respira- 
tion; and  as  the  action  of  the  muscles  and  of  the  nervous  sys- 
tem depends  greatly  on  respiration,  variations  in  this  function 
occasion  corresponding  ones  in  the  animal  function.  Thus  in 
the  mammalia,  where  the  circulation  is  double,  that  is,  where 
all  the  blood  brought  from  the  body  is  sent  to  the  lungs  be- 
fore returning  to  it,  and  where  respiration  is  aerial,  the  mus- 
cular action  is  strong.  In  birds,  where  the  circulation  is  dou- 
ble, and  where  respiration  is  aerial  also,  is  not  confined  to  the 
lungs,  but  extends  itself  to  various  parts  of  the  body,  the  vi- 
gour of  the  muscles  is  still  greater;  in  reptiles,  where  the  cir- 
culation is  simple,  and  respiration  consequently  partial,  it  is 
weak  and  the  movements  slow,  since  a  part  only  of  the  blood 
is  submitted  to  the  action  of  the  air,  previous  to  its  return  to 
the  body.  Fishes,  it  is  true,  have  a  double  circulation,  but 
their  respiration  can  not  be  complete,  on  account  of  the  small 
quantity  of  air  contained  in  the  water  they  respire,  conse- 
quently, as  to  station,  they  are  nearly  in  a  state  of  equilibrium 
in  water.  Animals  of  the  first  two  classes  have  much  warmer 
blood  than  those  of  the  two  latter,  which  on  this  account  are 
called  the  cold  blooded  vertebrata. 

Their  mode  of  generation,  presents  also  a  remarkable  differ- 


OF   VERTEBRATE   ANIMALS.  63 

ence,  from  which  the  vertebrata  are  divided  into  oviparous  and 
viviparous  or  mammalia. 

§  57.  The  oviparous  vertebrata,  are  particularly  alike  in 
their  mode  of  generation,  they  have  also  some  common  cha- 
racters of  organization  in  the  nervous  system,  and  in  the  bones 
which  envelop  it. 

Oviparous  generation  consists  essentially  in  the  germ  being 
inclosed  in  its  envelopes,  with  nutritious  matter  sufficient  to 
nourish  it  until  it  be  hatched,  so  that  if  the  egg  remain  in  the 
interior  it  does  not  attach  itself  to  the  parietes  of  the  oviduct, 
but  remains  separate.  The  nutriment  of  the  young  one  is  con- 
tained in  a  sac  which  is  a  part  of  its  intestine,  and  which  is 
called  the  yolk.  The  germ  is  at  first  a  mere  imperceptible  ap- 
pendage, but  as  fast  as  it  receives  its  nourishment,  it  increases 
in  size  by  the  absorption  of  the  yolk  which  is  proportionally 
diminished,  and  finally  disappears  near  the  period  of  hatching. 
The  embryos  of  the  ovipari  with  lungs,  birds,  and,  except  the 
batrachians,  reptiles,  have  moreover  a  very  vascular  membrane, 
which  appears  to  assist  in  respiration,  and  which  is  a  prolonga- 
tion of  the  bladder:  it  is  called  the  allantoid;  it  is  not  found 
either  in  fishes  or  the  batrachian  reptiles,  whose  young  are  pisci- 
form.  Particular  fish  and  reptiles  retain  their  eggs  within 
them  until  the  time  of  their  hatching;  such  are  called  ovovi- 
vipari. 

The  prolongation  of  the  spinal  marrow  in  the  cranium,  pre- 
sents in  the  ovipari,  highly  developed  tubercles,  called  the  quad- 
rigemina;  the  cerebrum  and  cerebellum,  on  the  contrary,  are 
very  slightly  so,  and  there  is  no  pons  varolii  nor  corpus  callo- 
sum.  The  bones  of  the  cranium  are  either  very  quickly  con- 
solidated, or  remain  a  long  time  divided;  their  senses  are  not 
as  perfect  as  those  of  the  vivipari;  the  lower  jaw,  which  is 
very  complex,  is  articulated  by  a  concave  facette  with  a  pro- 
jecting part  of  the  temporal  bone,  that  is  distinct  from  its  pe- 
trous portion;  the  orbits  are  only  separated  by  a  membrane  or 
a  bony  plate  of  the  sphenoid.  When  they  possess  anterior 
members,  the  clavicles  unite  and  form  a  fourchette  (as  the 
merry-thought  of  a  chicken)  while  the  elongated  coracoid  apo- 

physes  are  articulated  with  the  sternum.     The  larynx  is  sim- 
10 


»•* 

64  INTRODUCTION. 

pie,  and  has  no  epiglottis  &c.,  neither  is  there  a  complete  dia- 
phragm between  the  breast  and  the  abdomen. 

The  ovipari  are  divided  according  to  their  mode  of  respira- 
tion, their  temperature,  the  atmosphere  they  inhabit,  their  mo- 
tions, the  appendages  of  the  skin  &c.  into  three  classes:  Fishes, 
reptiles  and  birds. 

§  58.  Fishes  are  evidently  organized  for  natation;  they  are 
suspended  in  a  fluid  nearly  as  heavy  as  themselves.     Many, 
under  the  vertebral  column,  have  a  bladder  filled  with  air, 
which  by  its  own  contraction  or  dilatation  varies  the  specific 
gravity  of  the  animal.     The  head  variable  in  its  form,  is  of  a 
very  complicated  structure,  as  regards  the  cranium,  the  jaws, 
and  the  distribution  of  the  teeth.     The  limbs  are  abbreviated 
and  formed  into  fins;  other  fins  occupy  the  back,  the  top  of  the 
tail  and  its  extremity.     The  number  of  members  varies,  most 
generally  there  are  four,  sometimes  only  two,  and  in  some 
they  are  totally  wanting.     Their  position  and  connexion  with 
the  trunk  also  vary  greatly,  so  do  the  organs  of  digestion;  the 
pancreas  is  generally  superseded  by  intestinal   appendages. 
The  circulation  is  double,  i.  e.  all  the  blood  passes  through  the 
respiratory  organs,  but  the  atmosphere  respired  is  aerated  wa- 
ter: for  this  purpose,  they  have  on  the  sides  of  the  neck,  an 
apparatus  of  organs  called  branchiae.     These  are  leaflets  attach- 
ed to  little  lateral  arches  of  the  os  hyoides,  and  composed  of 
numerous  membranous  laminas,  covered  by  a  net-work  of  numer- 
ous blood-vessels;  this  opening,  is,  besides,  furnished  with  a 
branchial  membrane,  supported  by  the  processes  of  the  hoyoi- 
deus  and  a  bony  operculum.     The  water  which  the  fish  com- 
presses in  its  mouth  as  if  to  swallow  it,  escapes  between  the 
divisions  of  the  branchiae  and  acts  on  the  blood.     The  heart  has 
only  one  auricle,  which  receives  the  veins  of  the  body,  and  one 
branchial  ventricle.     The  blood,  after   having  traversed  the 
branchiae,  is  directed  into  a  large  vessel  under  the  spine,  which, 
exercising  the  functions  of  ventricle  and  aorta,  transmits  it  to 
every  part  of  the  body. 

Fishes  have  elongated  kidneys  stretched  along  the  sides  of 
the  spine  and  a  bladder.  Their  testicles  are  two  enormous 
glands,  generally  known  by  the  name  of  milts,  (laite)  their 


OP   VERTEBRATE   ANIMALS.  65 

ovaries  are  not  less  voluminous;  most  of  them  first  lay  their 
eggs,  and  afterwards  the  male  fecundates  them;  with  some, 
however,  copulation  and  an  intromission  of  sperm  takes  place, 
the  latter  heing  mostly  ovoviviparous.  The  muscles  which  form 
so  large  a  portion  of  the  mass  of  their  bodies  are  white,  exces- 
sively irritable,  and  are  less  perfectly  organized  than  those  of 
the  other  classes.  It  is  the  same  with  the  bones:  in  some  of  them 
(thechondropterygii)  the  bones  remain  cartilaginous:  the  cal- 
carious  substance  forms  no  filaments,  but  remains  in  isolated 
grains:  in  some  of  them,  even  the  articulations  of  the  spine  do 
not  exist,  and  iu  the  others,  the  bones,  although  fibrous  and 
calcarious,  differ  greatly  in  solidity,  and  are  remarkably  at 
variance  with  those  of  the  other  classes.  The  ribs  are  often 
soldered  to  the  transverse  apophyses.  The  senses  are  imper- 
fect; the  nostrils  are  mere  rudimental  pits  at  the  end  of  the 
nose;  the  cornea  of  the  eye  is  flat,  there  is  but  little  aqueous 
humour,  and  the  crystalline  is  almost  spherical;  the  ear  con- 
sists of  a  vestibulary  sac  in  which  are  suspended  bones  of  a 
stony  hardness,  and  in  three  semi-circular  membranous  canals, 
commonly  placed  in  the  hollow  of  the  cranium:  some  genera 
only  have  a  fenestra  ovalis,  opening  externally;  the  tongue  is 
most  commonly  bony  and  dentated,  or  horny;  the  whole  skin 
of  the  greater  portion  of  them  is  covered  with  scales.  Some 
have  fleshy  cirri  or  filaments,  which  may  serve  for  the  sense  of 
touch.  The  prolongation  of  the  spinal  marrow  into  the  cra- 
nium terminates  anteriorly  by  enlargements,  whence  originate 
the  olfactory  nerves. 

The  class  of  fishes  in  the  nature  of  the  skeleton,  and  in  the 
mode  of  generation,  offers  a  tolerably  well  defined  division, 
viz.  the  cartilaginous,  and  the  bony. 

It  is  in  this  class  of  the  vertebrata  that  we  find  a  genus  (that 
of  the  pleuronectes  or  flat  fishes)  where  the  head  is  defective  in 
symmetry,  such  as  the  two  eyes  being  on  the  same  side. 

§  59.  Reptiles  offer  in  their  figure,  in  their  structure,  and  in 
their  functions,  much  greater  varieties,  than  any  of  the  three 
other  classes  of  the  vertebrata.  In  fact,  some  have  four  feet, 
others  have  two  before,  a  third,  two  behind,  and  a  fourth, 
none  at  all.  In  some,  the  body  is  covered  with  scales,  in  others, 


tiU  INTRODUCTION. 

the  skin  is  naked.  Some  of  them  are  pisciform  in  their  fatal 
state,  and  as  they  advance  to  maturity  undergo  a  true  metamor- 
phosis. The  organs  of  digestion  greatly  vary;  the  circulation 
is  simple  and  the  respiration  partial, that  is,  the  heart,  otherwise 
very  variable,  transmits  the  blood  into  an  artery  of  which  one 
branch  only  goes  to  the  lungs,  the  result  of  which  is,  that  in 
each  circuit  of  the  blood,  a  part  of  it  only  is  submitted  to  res- 
piration. Their  lungs  are  shaped  like  bags,  or  at  least  have 
large  cells.  They  can  suspend  the  respiratory  process,  with- 
out stopping  the  circulation:  their  blood  is  cold.  The  quantity 
of  respiration  is  not  the  same  in,  this  class,  the  pulmonary  ar- 
tery not  being  in  all,  in  the  same  ratio  with  the  aortic  trunk 
from  which  it  arises.  They  have  a  trachea  and  larynx,  al- 
though voice  is  not  common  to  all:  the  alligator  is  another 
exception.  The  females  have  a  double  ovary  and  two  ovi- 
ducts. Some  males  have  a  bifurcated  penis,  others  have  none. 
None  of  them  hatch  their  eggs.  The  irritability  of  the  mus- 
cles is  such  that  it  continues  long  after  they  are  separated 
from  the  nervous  system,  and  even  from  the  rest  of  the  body. 
Their  sensations  are  obtuse.  Their  nostrils  traverse  the  face, 
but  the  ear  is  incomplete,  being  confined  to  a  vestibule  con- 
taining soft  bones,  the  semi-circular  canals,  and  in  some  a 
rudiment  of  a  cochlea.  We  also  find  under  the  skin  the  rudi- 
ments of  the  bone  of  the  tympanum.  The  crocodiles  alone  have 
an  external  auricular  opening.  The  brain,  which  is  small,  may 
he  taken  away  as  well  as  the  head,  and  motion  still  continue. 
Many  remain  torpid  during  a  part  of  the  year. 

From  their  great  variety  of  organization  reptiles  have  been 
divided  into  several  families. 

The  chelonia  or  tortoises,  have  a  heart  with  two  auricles, 
each  of  which  receives  a  different  blood,  and  with  one  ventri- 
cle, having  two  unequal  and  communicating  cavities,  in  which 
the  blood  from  the  auricles  is  mingled.  These  animals  are 
enveloped  by  an  upper  shell  formed  by  the  ribs  and  vertebral 
laminae,  and  by  an  under  one  formed  by  the  sternum,  both 
covered  by  the  skin,  and  by  a  horny  or  scaly  matter  exuded 
from  it.  In  respiration,  the  air  is  drawn  in  by  the  nostrils,  and 
forced  into  the  larynx  by  a  sort  of  deglutition.  The  male  has 
a  simple  canalated  penis.  The  female  lays  very  hard  eggs. 


OP  VERTEBRATE  ANIMALS.  67 

They  live  without  eating  for  months  and  even  years,  and  sur- 
vive decapitation  several  weeks. 

The  sauria  or  lizards,  crocodiles,  &c.,  have  hearts  resembling 
that  of  the  tortoise;  the  ribs  are  moveable  for  the  purpose  of 
respiration  and  the  lungs  greatly  extended.  The  eggs  have  an 
envelope  more  or  less  hard.  They  have  teeth,  nails  and  scales. 
The  penis  is  either  simple  or  double. 

The  ophidia  have  a  heart  with  two  auricles,  and  no  feet. 
Some  of  them  are  venomous.  Those  which  are  the  most  so 
have  insulated  fangs  and  a  peculiar  disposition  of  the  jaw. 
Their  superior  maxillary  bones  are  very  small,  placed  on  a 
long  moveable  pedicle,  analogous  to  the  external  pterygoid 
apophysis;  in  this  is  a  tooth  pierced  by  a  little  opening,  through 
which  is  ejected  the  poisonous  fluid  that  is  secreted  by  a  con- 
siderable gland  seated  under  the  eye.  This  tooth,  together 
with  several  reproductive  germs  of  the  same,  being  placed  on 
the  maxilla,  is  hidden  by  the  moveability  of  the  latter,  (when 
the  reptile  does  not  wish  to  use  it)  in  a  fold  of  the  gum. 

The  batrachians  or  frogs,  toads  and  salamanders  have  a  heart 
with  but  one  auricle,  and  one  ventricle.  They  have  lungs,  and 
while  young,  branchiae  similar  to  those  of  fishes.  In  this  first 
state,  the  circulation  is  like  that  of  fishes;  the  artery  is  divided 
and  distributed  in  the  branchiae;  the  vessels  there  unite  in  an 
aortic  trunk  which  supplies  the  body  and  even  the  lungs. 
When  the  branchiae  disappear  their  arteries  are  obliterated, 
with  the  exception  of  two  branches  which  unite  to  form  the 
aorta,  and  each  of  which  send  a  small  ramification  to  the  lungs. 
The  eggs  are  membranous,  and  are  fecundated  during  the  time 
of  their  being  laid  or  afterwards.  At  its  birth  the  young  one 
has  branchiae  and  no  feet;  the  first  disappear  as  it  advances  in 
age,  and  the  feet  are  developed.  Some  preserve  their  branchiae 
for  life. 

§  60.  Birds  are  evidently  organized  for  flight;  their  figure, 
the  proportion  of  their  parts,  their  great  powers  of  respiration, 
whence  result  their  specific  lightness  and  great  muscular  force, 
are  all  combined  for  this  mode  of  motion.  They  are  biped, 
their  anterior  members  being  solely  destined  for  flight.  The 
chest  and  abdomen  form  one  single  and  great  cavity,  whose 


68  INTRODUCTION. 

vertebrae  have  but  little  motion;  the  sternum  is  of  great  extent, 
and  still  further  augmented  by  a  projecting  blade,  resembling 
a  keel.     The  sternal  as  well  as  the  vertebral  part  of  the  ribs 
is  bony;  in  this  part  of  the  trunk  every  thing  is  disposed,  so  as 
to  give  a  solid  support  and  muscular  attachments  to  the  wings. 
The  shoulders  are  formed  by  the  merry  thought,  (the  four- 
chette)  the  ossa  coracokles,  which  are  very  strong,  and  by  elon- 
gated and  feeble  scapulae.     The  wing  is  supported  by  the  hu- 
merus,  the  two  bones  of  the  fore-arm  and  the  hand,  which  is 
lengthened  and  has  a  finger,  and  two  others  that  are  rudimental; 
it  has  a  range  of  elastic  quills.     The  pelvis,  which  is  very  long, 
furnish  insertions  for  the  muscles  of  the  inferior  members,  and 
its  bones  are  sufficiently  separated,  to  allow  room  for  the  de- 
velopment of  the  eggs.     The  lower  limbs  are  formed  of  the 
femur,  of  the  tibia,  and  of  the  fibula,  which  are  joined  to  it  by 
an  articulation  with  a  spring,  which  keeps  it  extended  without 
any  muscular  effort.     There  are  muscles,  also,  that  go  from 
the  pelvis  to  the  toes,  passing  over  the  knee  and  heel,  so  that 
the  toes  are  flexed  by  the  weight  of  the  body.     The  tarsus  and 
metatarsus,  are  formed  by  one  single  bone,  terminated  below 
by  three  pulleys.    There  is  most  generally  one  great,  and  four 
other  toes,  diverging  from  each  other,  the  number  of  whose 
joints  increase  from  the  great  one,  which  has  but  two,  to  the 
external  one,  which  has  five.     The  neck  is  lengthened,  is  com- 
posed of  many  vertebrae,  and  is  very  moveable;  the  coccygis 
is  extremely  short  and  furnished  with  quills  like  the  wings. 
The  brain,  whose  characters  are  similar  to  those  of  the  other 
oviparous  vertebrata,  is  remarkable  by  its  size,  as  compared  to 
that  of  the  body,  which  is  considerable;  but  this  does  not  de- 
pend upon  its  hemispheres,  which  are  small.     The  skin  of 
birds,  is,  commonly,  covered  with  feathers  composed  of  a  hol- 
low stem  and  barbs;  the  skin  is  scaly  on  the  superior  surface 
of  the  toes,  and  callous  beneath;  the  sense  of  touch,  must  con- 
sequently be  weak.    The  eye  is  furnished  with  three  moveable 
lids;  the  cornea  is  very  convex,  the  crystalline  lens  is  flat,  and 
the  vitreous  body  small.  The  crystalline  has  a  membrane  which 
appears  intended  to  move  it.     The  anterior  part  of  the  eye  is 
encircled  with  bony  pieces.    Birds  see  with  great  clearness, 


OF  VERTEBRATE  ANIMALS  69 

both  far  and  near.  The  ear  a  little  more  complete  than  in  the 
other  ovipari,  has  no  stones  in  the  vestibule;  the  cochlea  is 
somewhat  curved;  there  is  a  small  bone,  between  the  fenestra 
ovalis  and  the  tympanum,  which  is  deprived  of  a  conch,  ex- 
cept in  the  nocturnal  genera.  The  organ  of  smell,  concealed 
in  the  base  of  the  beak,  has  generally  three  cartilaginous  tur- 
binated  bones  and  no  sinus.  The  tongue  is  but  slightly  mus- 
cular, and  is  supported  by  a  bony  projection  of  the  hyoides. 
The  rings  of  the  trachea  are  entire,  at  its  bifurcation  there  is  a 
glottis  or  inferior  larynx,  where  voice  is  produced;  the  supe- 
rior larynx  is  very  simple.  The  lungs,  which  have  no  lobes, 
attached  to  the  ribs,  permit  air  to  pass  into  several  cavities  of 
the  body,  the  breast,  the  axillae,  and  even  of  the  bones;  this 
augments  their  specific  lightness  and  multiplies  respiration. 
The  upper  maxilla  is  principally  formed  by  the  inter-maxillary 
bones,  and  is  prolonged  backward  into  two  arches,  one  inter- 
nal made  by  the  ossa  palati,  and  the  other  external,  by  the 
maxillar  and  jugal  bones,  both  of  which  rest  on  the  square  or 
tympanal  bone,  which  is  moveable;  it  is  joined  to  the  craniu 
by  elastic  laminae.  Both  jaws  are  covered  with  horn,  whic 
supplies  the  want  of  teeth,  and  which  sometimes  has  their  form. 
The  stomach  is  composed  of  three  parts  more  or  less  distinct: 
the  crop,  which  is  sometimes  wanting,  the  membranous  stomach 
furnished  with  numerous  secretory  follicles,  and  the  gizzard, 
which  has  two  strong  muscles,  and  is  lined  by  a  coriacious 
membrane.  In  birds  of  prey,  however,  the  gizzard  is  very 
thin,  and  not  very  distinct  from  the  other  stomach.  The  spleen 
small,  the  liver  has  two  ducts,  and  the  pancreas  is  considera- 
te; there  are  two  appendages  to  the  rectum,  sometimes  one, 
md  in  some  genera  none,  which  appear  to  be  the  remains  of 

allantoid. 

The  rectum,  the  ureters,  and  the  spermatic  vessels  or  the  ovi- 
luct,  communicate  with  a  cavity  called  the  cloaca,  which  opens 
it  the  anus.  The  testicles  are  internal  and  under  the  loins ;  there 
is  but  one  ovary  and  one  oviduct.  Most  birds  copulate  by  the 
simple  approximation  of  the  anus;  some  genera,  however,  have 
a  small  canulated  penis.  The  egg,  detached  from  the  ovary, 
is  composed  of  the  germ  and  yolk  only;  it  becomes  enveloped 


70  INTRODUCTION. 

by  the  white  in  the  oviduct,  and  at  the  bottom  of  the  same 
canal  receives  its  shell.  The  heat  of  the  weather,  or  more 
commonly,  maternal  incubation,  develops  the  young. 

OF  THE  VIVIPAROUS  VERTEBRATED  ANIMALS. 

§  61.  Viviparous  vertebrata,  or  mammalia,  among  which  is 
man,  differ  from  the  ovipari,  not  only  in  their  mode  of  genera- 
tion and  in  their  quantum  of  respiration,  but  are  particularly 
distinguished  by  the  most  perfect  animal  functions,  and  a 
greater  intelligence,  less  under  the  domination  of  instinct, 
and  more  capable  of  perfectiveness. 

Their  general  conformation  is  that  of  the  vertebrata.  The 
splanchnic  cavity  of  the  trunk  is  divided  by  a  complete  muscu- 
lar partition  called  the  diaphragm.  With  one  single  exception, 
they  have  seven  vertebrae  in  the  neck;  they  have  a  sternum  to 
which  the  first  ribs  are  attached.  The  head  is  always  articu- 
lated with  the  first  vertebra  by  two  condyles.  The  cranium 
is  very  similar  in  its  composition.  The  occipital,  sphenoidal, 
ethmoidal,  parietal,  frontal  and  temporal  bones,  always  exist; 
in  the  foetus  several  of  these  bones  consist  of  different  pieces. 
The  face  also  has  but  little  variety;  it  is  essentially  composed 
of  the  superior  maxilla,  the  inter-maxillary  bones,  the  ossa  pa- 
lati,  the  vomer,  the  bones  of  the  nose,  the  inferior  ossa  turbi- 
nata,  and  of  the  jugal  and  lacrymal  bones:  these  united  form 
the  upper  jaw  which  is  fixed  to  the  cranium:  the  lower  one, 
formed  of  two  pieces,  is  articulated  by  projecting  condyles  to 
fixed  temporal  bones.  An  os  hyoides,  suspended  to  the  cra- 
nium by  ligaments,  supports  the  tongue,  which  is  always  fleshy. 
The  anterior  or  superior  members  originate  from  a  bony  cinc- 
ture or  shoulder,  formed  by  the  scapula,  not  articulated  with 
the  spine,  supported  in  many  of  the  mammalia  by  the  sternum, 
by  means  of  a  clavicle.  The  arm  is  formed  of  one  single  bone; 
the  fore-arm  of  two,  the  radius  and  ulna;  the  hand  which  ter- 
minates these  limbs,  is  composed  of  two  ranges  of  small  bones 
called  the  carpus,  of  a  range  of  bones  called  metacarpus,  and  of 
fingers,  each  of  which  consists  of  three  bones  called  phalanges. 
The  posterior  or  lower  limbs  are  similarly  formed,  and  this 


OP  VIVIPAROUS  VERTEBRATA.  71 

similarity  is  greater  or  less  in  proportion  as  the  functions  for 
which  the  limbs  are  destined,  are  more  or  less  alike.  Besides 
this,  in  all  the  mammalia,  with  the  exception  of  the  cetacea3, 
the  lower  limb  commences  by  a  bony  girdle  or  pelvis,  formed 
by  the  bones  of  the  hip  fastened  to  the  spine:  at  first  these 
bones  are  formed  of  three  distinct  parts,  the  illium,  the  pubis, 
and  the  ischium.  The  thigh  is  formed  of  one  single  bone,  the 
leg  of  two  principal  ones,  the  tibia  and  fibula;  the  foot  which 
terminates  this  member  is  composed  of  a  tarsus,  metatarsus, 
and  toes. 

The  muscles  possess  a  moderate  power  of  contraction;  but 
their  irritability  is  very  dependent  on  the  nervous  system. 
The  motion  is  that  of  walking.  Flight  can  take  place  in  some, 
by  means  of  elongated  limbs  and  extended  membranes;  while 
others  again,  having  their  limbs  very  much  shortened,  can  only 
swim.  The  nervous  system  of  the  mammalia  is  chiefly  charac- 
terized by  the  state  of  the  brain  and  cerebellum.  The  latter  has 
lateral  lobes  or  voluminous  hemispheres,  and  there  is  always  a 
pons  varolii  under  the  spinal  medulla.  In  like  manner  the 
cerebrum  always  has  the  corpora  striata,  and  is  formed  of 
two  voluminous  hemispheres,  furnished  with  circumvolutions, 
forming  two  lateral  ventricles,  connected  by  the  corpus  callo- 
sum. 

The  eyes,  lodged  in  the  orbits,  are  defended  by  two  lids, 
and  a  vestige  of  a  third;  the  sclerotica  is  simply  fibrous;  the 
crystalline  is  fixed  by  the  ciliary  processes.  In  all  of  them, 
the  ear  has  a  perfect  labyrinth,  with  a  cochlea,  a. drum  and 
a  membrana  tympani  and  small  bones.  The  nasal  fossa  tra- 
verse the  face,  have  the  ossa  turbinata,  and  extend  into  the 
sinuses  of  the  bones.  The  tongue  is  fleshy  and  attached  to 
the  os  hyoides.  The  skin  of  the  mammalia,  generally  is  co- 
vered with  hair;  the  cetaceae  alone  are  wholly  deprived  of  it. 

The  intestinal  canal  is  covered  with  the  peritoneum,  sus- 
pended to  the  mesentery,  a  fold  of  that  membrane  which  en- 
closes the  conglobate  glands  of  the  chyliferous  vessels,  and 
covered  with  a  floating  extension  of  the  same  membrane, 
called  the  epiploon.  They  have  a  urinary  bladder,  that 
opens,  with  very  few  exceptions,  into  the  orifice  of  the  organs 
11 


72  INTRODUCTION. 

of  generation.  The  cellular  lungs  and  the  heart  are  contained 
in  a  cavity  formed  by  the  ribs,  and  separated  from  the  abdo- 
men by  the  diaphragm,  where  the  surface  is  free.  The  circu- 
lation is  double,  and  respiration  aerial  and  simple.  There  is  a 
larynx  at  the  upper  extremity  of  the  trachea,  which  opens 
into  the  posterior  fauces,  this  communication  depending  on  a 
moveable,  fleshy  veil,  called  the  veil  of  the  palate,  or  the  ve- 
lum pendulum  palati. 

What  principally  distinguishes  the  organization  of  the 
mammalia,  is  their  generation.  It  is  essentially  viviparous, 
i.  e.  the  membranous  egg  descends  and  fixes  itself  in  the  ute- 
rus after  conception,  which  requires  a  coitus,  by  which  the 
sperm  of  the  male  is  thrown  into  the  organs  of  the  female. 
They  have  all,  like  other  vertebrate  vivipari,  at  least,  in  the 
beginning,  an  umbilical  or  intestinal  vesicle ;  they  have  also, 
like  the  lung'd  ovipari,  an  allantoid;  but  besides  this,  they 
have  other  envelopes,  the  superior  of  which,  the  chorion, 
fixes  itself  to  the  parieties  of  the  uterus  by  one  or  more 
plexuses  of  vessels,  called  placentas,  that  establish  a  communi- 
cation between  it  and  the  mother,  by  which  it  receives  nou- 
rishment, and  probably  oxygen.  When  the  foetus  has  acquir- 
ed the  necessary  developement,  it  is  expelled  with  the  rup- 
tured membranes.  The  mammae,  secretory  glands,  produce 
milk,  for  the  support  of  the  young,  as  long  as  they  need  it. 

It  is  to  this  kind  of  organization,  presenting,  however,  cer- 
tain variations,  that  man  belongs. 

§  62.  The  mammalia  have  some  organs  peculiar  to  them, 
such  as  the  hairs  of  the  skin,  and  the  mammae;  otherwise  they 
only  differ  from  the  other  vertebrata,  in  the  greater  deve- 
lopement of  certain  organs,  as  the  ear  for  instance,  the  brain, 
&c.,  or  by  different  combinations  of  the  organs  of  circulation, 
respiration  and  motion. 

The  blood  of  the  mammalia,  differs  from  that  of  the  ovipari 
in  the  form  of  its  coloured  particles ;  in  the  former,  they  are 
circular,  or  rather  lenticular;  whereas  in  the  latter,  they  are 
ovals,  or  flattened  ovoids. 

The  hairs  of  the  mammalia  are  not  essentially  different 
from  the  other  horny  appendages  of  the  skin:  like  all  organs 


OF  VIVIPAROUS  VERTEBRATA.  73 

of  this  description,  they  are  produced  by  an  excretion  on  the 
surface  of  that  membrane. 

The  mammae,  are  also  absolutely  similar  to  the  other  glan- 
dular secretory  organs. 

§  63.  The  mammalia,  however,  still  present  great  varieties 
in  their  organization;  either  in  the  organs  of  touch,  which 
are  the  more  perfect,  in  proportion  as  the  fingers  are  more 
numerous  and  pliable,  and  less  enveloped  by  the  nail ;  or  in 
the  organs  of  mastication,  and  consequently  in  the  rest  of  the 
digestive  organs,  or  finally,  in  the  organs  of  generation.  The 
different  combinations  of  these  varieties,  which  occasion  many 
others  in  all  the  functions,  and  even  in  the  intelligence  of  the 
animal,  have  caused  this  class  to  be  divided  into  several  orders, 
among  which  is  that  of  the  bimana,  formed  of  one  single 
genus,  Homo,  or  man. 

§  64.  Man  is  distinguished  from  the  other  mammalia,  by 
some  slight  differences  in  the  vegetative  functions,  by  some 
others,  more  important  in  the  organs  of  the  animal  functions, 
but  principally  by  his  intelligence. 

Intelligence,  which  distinguishes  man,  is  characterized, 
above  all,  by  consciousness,  reason  and  free  will,  by  a  moral 
sentiment,  and  that  of  a  divine  First  Cause. 

Besides  this,  of  all  the  mammalia,  man  has  the  hemispheres 
of  his  cerebrum  and  cerebellum,  the  most  greatly  developed, 
and  most  largely  furnished  with  circumvolutions.  This  vo- 
lume of  the  hemispheres,  appears  considerable,  particularly  in 
comparing  it  with  the  medulla,  the  nerves,  the  senses  and  the 
muscles.  His  cerebral  functions  are  greatly  developed,  and 
very  distinct  from  instinct.  He  is  gifted  with  speech,  and 
lives  in  society.  He  is  the  only  true,  two  handed,  and  biped 
animal;  his  whole  body  is  organized  for  a  vertical  position, 
and  his  hands  are  evidently  reserved  for  other  uses,  than  for 
standing  on. 

The  heart  is  directed  obliquely  over  the  diaphragm,  and  the 
aorta  somewhat  differently  arranged  from  that  in  the  quadru- 
peds. The  organs  of  digestion  are  fitted  for  a  varied  diet, 
principally  vegetable.  The  penis  is  free,  and  without  any  in^ 


74  INTRODUCTION. 

ternal  bone;  the  uterus  is  a  simple  oval  cavity  ;  the  mammae 
two  only  in  number,  are  seated  in  front  of  the  chest. 

But  as  the  remainder  of  this  work  is  devoted  to  an  exami- 
nation of  the  human  body,  it  would  be  superfluous  to  dwell 
upon  characters,  which  will  be  considered  in  their  proper 
places.  * 

SECTION  II. 

OF    THE    HUMAN   BODY. 

§  65.  Man,  as  is  evident,  partakes  of  the  general  characters 
of  bodies,  of  organized  beings,  of  animals,  of  the  vertebrata, 
of  the  mammalia ;  he  has  besides  this,  like  all  others,  those 
which  are  peculiar  to  him:  it  is  the  study  of  all  these  charac- 
ters, either  of  the  external  and  internal  conformation,  or  of  their 
phenomena,  that  constitutes  the  object  of  Anthropology,  or  the 
science  of  man.  The  immediate  end  of  human  anatomy,  also 
called  anthropotomy,  is  a  knowledge  of  the  body,  that  is  to 
say,  of  all  the  parts  that  compose  it,  and  of  their  mutual  ar- 
rangement. 

§  66.  The  anatomist  may  study  the  human  body  in  two 
different  states;  in  the  one  most  common,  that  proper  to  the 
species,  and  alone  compatible  with  health;  or,  on  the  contrary, 
in  its  deviations  from  the  natural  order.  In  the  first  instance, 
it  is  the  anatomy  of  the  healthy  man,  hygid  anatomy,  if  we 
may  so  express  it;  in  the  second,  it  is  morbid  anatomy. 

In  the  study  of  anatomy,  we  may  consider  the  whole  human 
body,  examine  the  general  characters  of  all  its  organs,  of  all  its 
humours,  &c. ;  these  are  the  general  views  of  anatomy.  We  may, 
by  uniting  the  multiple  organs,  in  genera,  or  in  systems,  accord- 
ing to  their  analogies  of  texture,  confine  ourselves  to  generic 
characters,  abstracting  all  the  specific  differences  of  the  organs; 
and  as  for  those,  which  without  being  mutiple,  are  extended 
to  all  the  body,  we  may  only  consider  the  general  characters, 
overlooking  the  local  differences  they  present  in  the  various 

*  Vide  Blumenbach  "de  varietate  nativa  generis  humane — Laurence, 
"Lectures  on  Physiology,  Zoology  and  the  natural  history  of  man. 


OF   THE   HUMAN  BODY.  75 

regions;  such  is  general  anatomy;  it  imparts  a  knowledge  of 
the  subject,  a  little  more  precise,  than  the  more  general  view 
above  mentioned.  But  in  order  to  know  the  human  body, 
in  a  positive  and  useful  way,  we  must  add  to  this,  an  exact 
knowledge  of  each  organ,  in  particular,  and  of  each  of  its  re- 
gions;— such  is  the  object  of  special  anatomy. 

General  anatomy,  considering  together  the  organs  similar  as 
to  their  texture,  and  confining  itself  to  what  may  be  generic  or 
common  to  them  all,  has  for  its  special,  but  not  its  only  object, 
their  texture.  The  special  anatomy  of  the  organs,  improperly 
styled  descriptive  anatomy,  treats  particularly  of  their  con- 
formation, for  it  is  principally  in  this,  that  they  differ  from  each 
other;  their  respective  situations,  is  the  essential  object  of 
topographical  anatomy,  or  the  anatomy  of  the  regions. 

§  67.  The  external  form  of  the  human  body,  is  symmetri- 
trical;*  it  is  divided  into  two  lateral  similar  halves,  by  a  me- 
dian verticle  line.  This  line  is  even  marked,  in  some  places, 
where  it  forms  what  are  called  raphae  or  seams,  which,  in 
fact,  appears  to  result  from  a  sort  of  sewing,  or  junction  of 
the  two  lateral  portions,  originally  separated.  This  symme- 
try is  not  equally  perfect  in  all  parts  of  the  body;  it  is  more 
so  in  the  organs  of  animal  functions,  and  less  so  in  those  of  the 
vegetative  functions,  particularly  in  those  of  nutrition.  In 
fact,  the  bones,  the  nervous  system,  the  senses,  and  the  mus- 
cles, are  the  most  symmetrical  parts,  while  the  organs  of  di- 
gestion, of  circulation,  and  of  respiration,  are  less  so  than  the 
genital  organs.  It  would  not  be  exactly  correct,  however, 
to  say  that  symmetry  belongs  to  the  former,  and  is  foreign  to 
the  latter ;  it  belongs,  generally,  more  to  the  external  parts, 
and  is  less  perfect  in  those  that  are  deeply  seated;  thus  the 
lachrymal  and  salivary  glands,  the  thyroid  gland,  the  mammae, 
the  testicles,  and  all  the  organs  of  the  functions  of  nutrition  and 
generation,  are  symmetrical;  while  the  nerves  of  the*larynx, 
of  the  stomach,  of  the  intestines,  and  the  diaphragm,  are  not. 
It  is  also  to  be  observed,  that  certain  parts,  which  are  develop- 
ed at  a  later  period  are  less  symmetrical  than  those  of  the 

*  See,  among  others,  Bichat,  Reck.  Physiol  sur  la  vie  and  la  mort- 
Meckel,  Beitz.  zur  vergl.  anat.  Leipz.  1812. 


76  INTRODUCTION. 

same  kind,  which  are  previously  developed:  thus,  in  the 
nervous  system,  the  medulla,  which  is  first  developed,  is  more 
symmetrical  than  the  brain  ;  the  ribs  are  less  symmetrical  than 
the  spinal  column,  and  more  so  than  the  sternum.  Finally,  we 
may  further  observe,  that  the  parts  are  most  symmetrical  at  the 
period  of  their  formation,  and  that  this  kind  of  regularity, 
afterwards  changes:  the  stomach,  intestines  and  liver,  are 
less  irregular  at  first,  than  at  a  later  period;  the  vertebral 
column,  at  first  exactly  median,  gradually  inclines  to  the  left, 
from  the  predominance  of  the  right  arm,  and  thence  results 
the  inclination  of  the  nose,  the  unequal  elevation  of  the  testi- 
cles, the  frequency  of  hernia  on  the  right  side,  &c.  Sometimes 
such  a  derangement  of  this  symmetry  is  observed,  that  the  or- 
gans of  one  side,  occupy  the  other,  and  vice  versa;  this  is  called 
a  transposition  of  the  viscera.  In  this  case,  which  happens  in 
about  one,  of  three  or  four  thousand  subjects,  and  that  I  have 
seen  four  or  five  times,  the  trilobated  lung,  the  liver  and  the 
ca3cum,  are  on  the  left,  while  the  bilobated  lung,  the  apex  of 
the  heart,  the  spleen,  the  sygmoid  portion  of  the  colon,  &e. 
are  on  the  right:  Individuals  thus  situated,  are  not,  however, 
left-handed  on  this  account.  The  diseases,  which  affect  the 
symmetrical  organs,  and  those  whose  seat  is  in  parts  that 
are  not  so,  present  a  very  remarkable  difference.  It  has  been 
even  asserted,  but  upon  hypothetical  views,  that  each  side  of 
the  body,  has  a  greater  predisposition  to  certain  maladies,  than 
its  fellow.* 

Comparisons  have  also  been  established,  and  analogies  sought 
for,  between  the  upper  and  lower  halves  of  the  body.  The 
analogy  between  the  limbs  is  evident;  the  shoulders  and  pel- 
vis, the  leg  and  the  arm,  the  hand  and  the  foot,  are  construct- 
ed on  one  plan,  and  differ  only  so  far  as  their  different  func- 
tions require.  As  to  the  analogy,  supposed  to  have  been 
found  in  man,  as  in  the  articulata,  between  different  sections 
of  his  trunk,  and  between  the  limbs,  and  the  jaws,  it  rests  on 
a  comparison  between  objects  too  dissimilar  to  admit  of  it. 

Carried  away  by  a  forced  analogy  with  the  radiata,  anato- 

*  See  Mehlis,  de  rnorbis  Jiominis  dextri  et  sinistri.  Getting.  1818. 


OF    THE    HUMAN    BODY.  77 

mists  have  sought  for  parts  in  the  anterior  portion  of  the  trunk, 
corresponding  to  the  vertebral  column;  they  think  they  have 
found  them  in  the  sternum:  observation  here  shows  no  rea- 
sonable approximation,  except  between  ihe  anterior  and  pos- 
terior muscles  of  the  spine.  Let  us  abandon  then,  compari- 
sons which  can  tend  to  no  good  or  useful  purpose. 

§  68.  The  human  body  is  divided  like  that  of  the  other 
vertebrata,  into  trunk  and  members.  The  trunk  is  the  cen- 
tral and  principal  part,  that  which  contains  the  organs  most 
essential  to  life^  or  the  viscera.  These  parts  are  lodged  in 
three  cavities;  the  inferior  is  the  abdomen,  and  contains  the 
organs  of  digestion,  of  the  urinary  secretion,  and  of  genera- 
tion; the  middle  one,  the  thorax,  contains  the  organs  of  respi- 
ration and  circulation,  while  the  superior,  the  head,  whose 
cavity  is  continued  into  the  vertebral  column,  contains  the 
nervous  centre  and  the  senses.  It  may  have  been  already  re- 
marked, (sec.  1,)  how  much  this  distribution  of  the  viscera  is 
in  relation  with  their  importance  in  the  animal  kingdom. 
We  shall  see  hereafter,  that  it  is  equally  so  with  the  order  of 
their  developement.  Considered  as  a  whole,  the  trunk  from 
before  backward,  presents  a  face  anterior  or  external,  one  pos- 
terior or  dorsal,  and  sides;  it  presents  two  extremities,  the  one 
superior  or  cephalic,  the  other  inferior  or  pelvic.  The  limbs 
or  members,  articulated  appendages,  destined  for  motion,  are 
divided  into  superior  or  thoracic,  and  inferior  or  abdominal, 
both  being  divided,  in  several  places,  by  articulations.  The 
different  portions  of  the  trunk  and  members,  are  again  subdi- 
vided into  a  certain  number  of  regions  or  parts,  all  distinct 
and  important,  on  account  of  the  organs  placed  there.  These 
divisions  and  subdivisions  of  the  body,  are  principally  deter- 
mined by  the  bones.  A  knowledge  of  the  regions  is  neces- 
sary, in  order  to  determine  the  exact  situation  of  the  organs, 
and  their  profound  study,  the  surest  or  rather  the  only  means 
of  knowing  the  respective  situation  of  parts:  this  knowledge 
constitutes  a  sort  of  topographical  anatomy,  which  is  of  the 
greatest  importance. 

§  69.  The  human  body,  like  all  those  that  are  organized, 
is  composed  of  solid  and  fluid  parts,  which  have  a  similar 


78  INTRODUCTION. 

composition,  and  which  are  continually  changed  into  each 
other.  The  fluids  are  very  abundant,  and  their  mass  is  great- 
ly superior  to  that  of  the  solids.  The  exact  proportion  of  the 
one  to  the  other,  however,  can  not  he  determined,  because  on 
the  one  hand,  certain  fluids,  as  oil,  separate  from  the  solids 
with  great  difficulty,  and  on  the  other,  many  of  the  solids  can 
be  rendered  fluid,  and  during  dessication,  disappear  among 
the  fluids,  and  are  dissipated  with  them.  To  determine  this 
proportion  of  the  liquids  to  the  solids,  however,  attempts  have 
been  made,  both  by  dessicating  the  parts  in  stoves  or  ovens, 
and  by  mummifaction;  some  have  considered  the  proportion 
as  six  of  the  fluids,  to  one  of  the  solids,  while  others  place  it 
as  nine  to  one.  The  examination  of  a  mummy,  gave  a  still 
greater  proportion,  as  this  adult  mummy  weighed  only  seven 
and  a  half  pounds.  But  could  the  proportion  be  exactly 
ascertained  in  any  one  case,  it  would  vary  according  to'the 
individual,  the  age,  sex,  constitution  &c.,  inevitably  occasion- 
ing a  marked  difference. 

Both  the  solids  and  fluids  are  formed  of  globules,  and  of  an 
amorphous  substance,  liquid  in  the  one,  and  concrete  in  the 
other. 

§  70.  The  chemical  composition*  of  the  solids  and  fluids  of 
the  human  body,  results  from  a  certain  number  of  immediate 
materials,  the  chief  of  which  are  gelatine,  albumen,  mucus, 
fibrine,  oil,  water,  sugar  resin,  urea,  picrocholine,  osmazome, 
zoohematine,  phosophate  and  carbonate  of  lime,  &c.  These 
substances  themselves  are  compound,  and  the  ultimate  elements 
found  in  the  human  body,  are  oxygen,  hydrogen,  carbon,  nitro- 
gen, phosphorus,  calciunijsulphur,  potassium,  sodium,  chlorine, 
iron  and  manganese — we  even  find  magnesium  and  silicium. 

These  elementary  substances,  in  order  to  form  the  imme- 
diate materials,  and  these  latter,  to  compose  the  solid  and  fluid 
parts  of  the  human  body,  are  combined  in  the  acts  of  nutrition 
and  generation  in  a  way  that  chemistry  can  not  imitate:  and  it 
is  precisely  this  act  of  formation  or  organization  that  charac- 
terizes life. 

*  See  Orfila.  Chimie  Medicale. 


OF  THE  FLUIDS.  79 

OF  THE   FLUIDS. 

§  71.  The  fluids,  or  the  humours*  of  the  human  body,  are 
contained  in  the  solids,  and  penetrate  all  their  parts.  They 
are  composed  of  molecules,  coming  from  without  for  the  sup- 
port of  the  body,  and  of  those  which  are  detached  from  it  to 
be  rejected.  Their  fluidity  is  owing,  not  only  to  caloric  and 
water,  like  that  of  fluids  foreign  to  the  organization,  but  like 
their  composition,  it  depends  upon  the  vital  action.  The  fluids 
differ  from  each  other,  one  being  gaseous,  another  vaporous, 
and  a  third  a  liquid  more  or  less  flowing;  they  also  differ  in 
colour;  their  composition  too  varies,  but  it  is  peculiar  to  them, 
and  can  not  be  imitated  by  art. 

The  fluids  may  be  divided  into  three  kinds,  1st,  the  blood,  a 
central  mass,  to  which  flow,  and  from  which  emanate  all  the 
others;  2d,  the  humours  which  go  to  the  blood  from  without; 
3d,  those  which  emanate  from  it. 

§  72.  The  blood  is  a  liquid  of  a  red  colour,  and  of  a  peculiar 
odour;  it  has  a  nauseous  and  slightly  saline  taste;  its  tempera- 
ture is  that  of  the  body,  of  which  it  is  even  the  warmest  por- 
tion; it  is  viscid  to  the  touch;  its  specific  gravity  is  about  105, 
water  weighing  100.  It  is  contained  in  the  heart,  and  san- 
guiferous  vessels.  Its  quantity  in  the  adult  is  considerable,  but 
variable.  This  quantity  has  been  very  differently  estimated, 
varying  from  eight  or  ten  pounds,  to  eighty  or  a  hundred. 

§  73.  Microscopic  observers  have  made  the  following  ob- 
servations upon  this  fluid:  the  blood  is  composed  of  a  serous 
vehicle  in  which  red  microscopic  globules,  are  held  in  suspen- 
sion; these  bodies  have  been  generally  considered,  either  as 
spheres,  marked  with  a  luminous  point  in  the  centre,  or  as  be- 
ing pierced  and  consequently  of  ao  annular  form.  Hewson,  on 
the  contrary,  conceived  the  red  particles  of  the  human  blood  to 
be  lenticular.  The  important  observations  of  Messrs.  Prevost 
and  Dumas  and  my  own,  have  given  the  same  result.  Mr. 
Home,  like  Dr.  Young,  considered  the  flattening  as  subsequent 

*  See  Plenck.  Hygrologia  corporis  humani — Chaussier.  Table  synoptiquc 
des  humeurs. 

12 


80  INTRODUCTION. 

to  the  exit  of  the  blood,  and  that  it  depended  on  its  separation 
from  the  colouring  matter.  The  particles,  are,  in  fact,  com- 
posed of  central  globules,  transparent,  whitish,  and  with  a  red 
envelope,  less  diaphanous,  formed  like  compressed  spheres-, 
The  diameter  of  the  particles,  in  the  human  species,  is  about 
the  one  hundred  fiftieth  of  a  millimetre.  As  long  as  the  blood 
is  contained  in  the  vessels,  and  is  in  motion  there,  things  re- 
main in  this  state. 

§  74.  The  blood,  out  of  its  vessels,  and  while  it  retains  its 
warmth,  exhales  a  vapour  formed  of  water,  and  of  an  animal 
matter  susceptible  of  putrefaction.  It  soon  coagulates,  yield- 
ing, probably,  a  little  warmth,  and  gives  out  a  large  quan- 
tity of  carbonic  acid  gas.  This  disengagement  of  the  gas,  but 
little  sensible  while  the  blood  is  subjected  to  atmospheric  pres- 
sure, manifesting  itself  only  by  the  formation  of  canals  in  the  in- 
terior of  the  coagulum,  takes  place  on  the  outside  of  the  clot, 
when  it  is  placed  under  the  exhausted  receiver  of  the  air 
pump.  We  must  not  confound  this  extrication  of  gas  and  va- 
pour from  the  blood  when  taken  from  its  vessels,  with  a  pre- 
tended gas  that  has  been  supposed  to  circulate  with  it. 

Shortly  after  the  blood  has  coagulated  into  a  single  mass,  it 
separates  into  two  parts;  the  coagulum  contracting,  presses  out 
the  fluid  part  or  the  serum,  it  contained.  This  contraction 
continues,  and  consequently,  the  quantity  of  this  expressed  se- 
rum augments  until  putrefaction  takes  place.  Generally  the 
upper  surface  of  the  coagulum,  contracting  more  than  the  rest, 
becomes  concave.  If  the  clot  be  held  for  a  long  time  under  a 
small  stream  of  water  and  gently  pressed,  the  water  carries 
away  the  colouring  matter  or  cruor,  and  there  remains  a  white 
fibrous  mass.  Thus  by  coagulation  and  washing,  the  blood  is 
divided  into  serum,  cruor,  and  fibrine. 

But  let  us  see  what  takes  place  during  these  operations:  as 
soon  as  the  blood  is  out  of  its  vessels,  the  colouring  matter  of 
the  particles  leaves  the  central  white  globules,  and  tho  latter, 
deprived  of  their  envelope,  unite  to  each  other  and  form  fila- 
ments which  interweave  themselves,  forming  a  net-work,  in 
which  are  contained  both  the  colouring  matter,  and  many  en- 
tire particles  that  have  not  undergone  this  decomposition. 


OP  THE  FLUIDS.  .          81 

During  the  washing  and  squeezing  of  the  clot,  both  the  free 
colouring  matter,  and  particles  that  remain  entire,  and  that 
contain  white  globules  in  their  centres,  are  carried  away  by 
the  water  at  the  same  time. 

The  blood,  then,  contains  three  principal  materials,  the  se- 
rum, the  white  globules,  and  the  colouring  matter  that  en- 
velops them:  the  two  last  united  in  the  fluid  blood,  and  form- 
ing the  colouring  particles,  separate,  in  a  great  measure,  soon 
after  the  blood  is  drawn  from  the  vessels.  These  materials 
are  in  very  different  proportions,  according  to  the  various  cir- 
cumstances of  age,  sex,  constitution,  disease,  &c.  &e. :  in  the 
adult  and  healthy  man,  the  dried,  colouring  particles  consti- 
tute a  little  more  than  an  eighth  of  the  total  weight  of  the 
blood. 

§  75.  The  serum  has  a  pale,  yellowish  green  colour;  it  has 
the  taste,  smell,  and  feel  of  blood;  it  is  alkaline;  it  coagulates 
at  about  69°.  C.    It  then  resembles  the  white  of  a  cooked  egg, 
and  contains  in  its  vacunse,  a  substance  that  has  been  taken  for 
gelatine,  and  which  appears  to  be  mucus.     The  constituent 
parts  of  the  serum  are,  water,  albumen,  soda,  and  salts  of  soda. 
According  to  M.  Brand,  we  may  consider  the  serum,  which  is 
a  liquid,  and  almost  pure  albumen,  as  an  albuminate  of  soda 
with  an  excess  of  base.     The  coagulation  appears  to  depend 
upon  the  neutralization  of  the  souda  necessary  to  its  fluidity; 
alcohol  and  most  of  the  acids,  produce  this  coagulation  by  re- 
moving the  soda;  and  by  the  action  of  the  galvanic  pile  as  well 
as  by  that  of  heat,  the  soda  transforms  a  small  portion  of  the 
albumen  into  mucus,  while  the  remainder  coagulates.     The 
albumen  and  the  serum  itself,  still  present  some  peculiarities 
worthy  of  remark;  it  is  that  coagulated  albumen,  presents  glo- 
bules under  the  microscope,  and  that  the  serum,  preserved  in 
a  liquid  state,  in  a  proof  glass  for  a  few  days,  gradually  pro- 
duces globules,  that  are  deposited  at  the  bottom,  and  which  ex- 
perience a  singular  movement  of  ascent  and  descent,  on  heat- 
ing the  glass  by  holding  it  in  the  hand;  we  must  also  observe, 
that  coagulated  albumen,  has  the  closest  analogy  with  fibrine, 
from  which,  perhaps,  it  does  not  in  any  way  differ. 
§  76.  The  cruor  of  the  blood,  or  the  colouring  matter  obtain- 


82  INTRODUCTION. 

ed  by  washing  it,  is  always  a  mixture  of  the  free  red  matter  of 
the  globules  enveloped  in  the  same  matter,  and  of  serum.  We 
consequently  find,  that  the  most  able  chemists,  have  as  yet, 
learned  but  little  respecting  Jhe  colouring  matter  of  the  blood, 
or  the  zoohematine.  This  substance,  insoluble  in  water,  but 
capable  of  an  extraordinary  division  in  it,  so  as  to  pass  through 
the  filter,  is  composed  of  an  animal  matter  in  combination  with 
the  peroxide  of  iron.  The  red  colour  of  the  blood  has  different 
shades. 

§  77.  The  fibrine  of  the  blood,  or  the  coagulable  lymph  of 
some  authors,  resembles  tenacious  elastic  downy  fibres,  pre- 
senting under  the  microscope  the  aspect  of  the  muscular  fibre, 
being  composed  of  white  globules  similar  to  those  of  the  co- 
loured particles  of  the  blood;  the  fibYine  also,  like  the  muscular 
fibre,  being  placed  in  water,  resolves  itself  into  globules  pre- 
vious to  putrefaction.  This  coagulable  or  plastic  substance, 
as  well  as  albumen,  appears  to  be  the  medium  of  agglutination 
which  occasions  the  reunion  and  adherence  of  divided  parts 
of  the  body. 

The  blood  contains  also  a  fatty  or  oily  matter. 

§  78.  The  blood  contained  in  the  arteries,  veins,  and  heart, 
is  constantly  in  motion;  this  is  called  the  circulation.  During 
this  movement,  it  undergoes  constant  and  regular  changes, 
which,  being  exactly  balanced,  preserve  it  in  a  medium  state  of 
composition.  It  receives  new  liquids,  prepared  by  digestion 
and  intestinal  absorption;  molecules  separated  from  the  organs, 
are  unceasingly  added  to  its  mass;  it  is  submitted  to  the  action 
of  the  atmosphere  in  the  lungs,  where  it  is  revivified;  it  is  then 
sent  to  all  parts  of  the  body,  where  it  undergoes  an  inverse  al- 
teration, where  it  furnishes  materials  that  fix  themselves  in  the 
organs,  and  where  it  is  deprived  of  a  part  of  its  principles  by 
the  secretions.  Amid  all  these  changes,  none  are  so  striking 
as  those  it  undergoes  in  the  lungs,  where  it  becomes  of  a  bright 
red  or  vermillion,  and  in  the  remainder  of  the  body  where  it 
assumes  a  reddish  brown  colour.  These  alterations  of  colour, 
appear  to  depend,  in  the  first  case,  upon  an  absorption  of  oxy- 
gen, and  in  the  second,  of  carbone.  Besides,  the  nutritive 


OF  THE  FLUIDS.  83 

principle  which  the  blood  distributes  to  all  the  organs,  it  is  also 
the  vehicle  of  the  warming  principle. 

§  79.  The  blood  varies  steadily  according  to  the  age,  sex, 
and  other  circumstances;  it  also  offers  accidental  changes. 

In  the  foetus,  the  blood,  which  is  very  dark,  has  scarcely 
any  coagulable  matter.  It  is  the  same  with  the  menstrual 
blood  of  women.  Arterial  has  a  greater  proportion  of  coloured 
particles  than  veinous  blood.  In  those  individuals  that  use 
succulent  food,  the  blood  abounds  with  clot;  it  is  more  serous 
under  opposite  circumstances.  The  repeated  abstraction  of 
blood,  diminishes  the  proportion  of  the  coloured  particles,  and 
even  the  albumen,  but  it  augments  that  of  the  water. 

In  disease,  the  blood  suffers  changes  that  have  not  been  suf- 
ficiently studied.  In  inflammations,  the  clot  of  the  extracted 
blood  becomes  covered  with  a  white  coat,  this  is  the  fibrine: 
and  in  the  clot  is  also  to  be  seen  a  large  quantity  of  free  colour- 
ing matter.  In  particular  cases,  such  as  the  scurvy,  and  in 
septic  disorders,  the  blood  loses  its  coagulability,  it  remains 
fluid.  There  are  many  diseases  on  which  an  attentive  exami- 
nation of  the  blood  would  throw  great  light. 

§  80.  The  liquids  poured  into  the  blood  are  the  chyle  and 
the  lymph.  The  first  comes  from  the  chyme,  a  grayish,  pul- 
taceous  substance,  into  which  the  aliments  are  changed  in  the 
stomach,  and  in  which  little  globules  begin  to  appear.  Ab- 
sorbed by  the  parietes  of  the  intestine,  and  having  arrived  in 
the  first  chiliferous  vessels,  it  is  whitish  and  hardly  coagula- 
ble, it  becomes  more  so,  and  assumes  a  rosy  tint  in  the  glands 
of  the  mesentery.  Finally,  when  in  the  thoracic  duct,  and 
ready  to  pass  into  the  blood,  it  is  distinctly  of  a  rose  colour, 
evidently  coagulable,  and  contains  naked  globules  and  parti- 
cles, which  differ  from  those  in  the  blood,  only  by  an  inferior 
strength  of  colour.  It  seems  thenceforward  to  need  nothing 
but  the  respiratory  process  to  become  perfect  blood.  The 
lymph,  a  colourless,  viscid,  albuminous  liquid,  but  little  un- 
derstood, is  the  remaining  fluid  carried  to  the  blood. 

§  81.  The  humours  which  emanate  from  the  blood,  are  se- 
parated from  it  by  secretion.  We  may  consider  the  nutritive 
matter  left  by  the  blood  in  all  the  organs,  as  being  of  this  class; 


S4  INTRODUCTION. 

we  may  also  add  to  it,  those  which  are  produced  and  deposit- 
ed, as  if  in  reserve  (by  a  secretion  that  we  may  call  intrinsic.) 
in  the  closed  cavities  of  the  body,  such  as  fat,  serosity,  syno- 
via; but  we  principally  attach  to  it  those  which  are  secreted 
on  the  surface  of  the  teguments,  external  or  internal,  and  of 
their  appendages  more  or  less  removed.  From  their  mode  of 
formation,  we  divide  them  into  three  classes  or  kinds:  1st,  in 
perspiratory  humours,  which  are  immediately  formed  and  de- 
posited on  the  surface  by  the  vessels:  such  is  the  matter  of  cu- 
taneous transpiration,  of  sweat,  of  the  pulmonary  perspiration; 
2d,  in  the  follicular  humours,  which  at  first  are  deposited  in 
the  follicles  of  the  skin,  internal  or  external:  such  are  the  mu- 
cus, and  the  sebaceous  matter;  and  3d,  in  glandular  humours, 
formed  in  the  glands,  peculiar  organs,  which  have  excreting 
ramifying  ducts  opening  on  the  skin  and  mucous  membranes, 
of  which  they  are  prolonged  ramifications:  such  are,  the  saliva, 
secreted  by  the  salivary  glands,  the  bile  secreted  by  the  liver 
&c.  We  also  divide  the  secreted  humours,  from  their  desti- 
nation into  those  which  take  part  in  the  organism,  as  the  tears, 
bile,  sperm,  etc.,  and  into  those,  which  being  rejected  without 
answering  any  purpose  whatever,  are  called,  excrementitious. 
These  last  are  acid,  whereas  the  others  are  alkaline. 

OF  THE  ORGANS. 

§  82.  The  organs  are  the  solid*  or  the  containing  parts  of 
the  body;  they  it  is  which  above  all,  determine  the  form  of 
the  body,  and  which  direct  its  motions. 

The  figure  of  the  organs  is  greatly  varied :  generally  speak- 
ing, however,  their  contour  is  rounded;  the  surfaces  are  never 
perfect  planes,  the  lines  very  straight,  or  the  angles  very  en- 
tire. In  the  generality  of  them,  the  length  is  greater  than 
that  of  the  two  other  dimensions;  some  are  large  and  flattened: 
those  that  have  this  form  and  are  soft,  are  called  membranes, 
whatever,  in  other  respects,  may  be  their  texture;  others  again 
have  but  little  difference  in  their  three  dimensions.  We  de- 
termine the  external  form  of  the  organs  by  the  relation  of 

*  See  Chaussicr.  Tublc  dcs  solides  organiques. 


OP  THE  ORGANS.  85 

their  three  dimensions;  we  often  also,  use  comparisons  more 
or  less  trivial:  for  most  commonly  it  is  rather  difficult  to  de- 
termine the  form  by  a  comparison  with  geometrical  figures. 

In  the  interior,  some  organs  are  hollow,  and  form  reservoirs 
or  canals  opening  externally;  others  form  cavities  closed  on  all 
sides;  a  third,  ramified  and  closed  canals,  a  fourth  is  full  or 
massive :  but  they  are  all  areolar,  and  more  or  less  perme- 
able. 

Among  the  organs,  there  are  some  which  extend  them- 
selves, branching  or  radiating  from  the  centre  to  the  circum- 
ference: such  are  the  vessels,  nerves,  and  the  bones  themselves. 
None  i.s  insulated,  all  are  interlaced  and  communicate  with 
each  other.  Finally,  there  is  a  great  analogy  between  the 
organs,  as  well  as  the  regions.  Some  of  them  being  exactly 
similar,  by  their  union,  constitute  genera. 

§  83.  The  colours  of  the  organs  are  white,  red  and  brown; 
some  of  them  are  transparent,  others  opaque.  Their  consis- 
tence varies  from  great  softness,  to  an  extreme  hardness. 
They  are  extensible  and  retractile,  flexible,  compressible  and 
elastic,  but  in  very  different  degrees.  The  cohesion  of  some 
is  but  slight,  while  others  are  endowed  with  such  tenacity  as 
to  require  very  great  efforts  to  break  them.  These  properties 
of  colour  and  cohesion  depend  much  on  the  liquids  which 
they  in  a  great  measure  contain.  Thus  opaque  parts,  such  as 
the  ligamentous  tissue,  become  transparent  by  dessication ; 
this  same  substance,  very  tenacious  and  but  little  elastic  when 
humid,  becomes  greatly  so  when  dried  ;  elastic  parts,  such  as 
the  tissue  of  the  arteries  become  brittle  by  dessication,  &c. 

§  84.  The  organs  differ,  also,  greatly  with  regard  to  their 
texture.  At  the  first  glance,  we  see  that  several  of  them  are 
formed  by  the  reunion  of  bundles  of  parallel  or  interwoven 
threads — we  then  say  their  texture  is  fibrous.  Others  are 
formed  by  the  union  of  layers  or  laminae  more  or  less  numer- 
ous and  distinct,  and  usually,  closely  united.  In  others  again 
we  find  granulations  or  approximated  grains  closely  united 
with  each  other.  Some  of  them  have  apparently  a  very  com- 
pact, uniform  or  homogeneous  texture,  but  it  is  in  appearance 


86  INTRODUCTION. 

only;  for  all  are  areolar  and  permeable  more  or  less  distinct, 
all  are  more  or  less  compound, 

§  85.  This  first  view  of  the  subject  is  not  sufficient  to  show 
the  exact  texture  of  the  solid  parts.  By  a  closer  examination, 
we  perceive  that  these  apparent  fibres,  these  membranous  layers, 
these  granulations,  are  themselves  compound;  and  as  the  solids 
contain  the  humours,  it  has  been  generally  believed,  that  there 
is  nothing  but  vessels  in  the  solids.  This  erroneous  idea,  for 
the  vessels  themselves,  are  compound  parts,  has  been  recently 
revived  in  a  posthumous  work  of  Mascagni.  Other  authors 
have  admitted  that  every  thing  is  formed  of  the  cellular  tissue, 
and  this  by  interwoven  layers  and  fibres,  or  by  cells  or  vesi- 
cles adhering  to  each  other.  But,  the  cellular  tissue,  although 
it  is  the  principal  element  of  all  the  parts,  is  not  the  only 
one.  As  to  the  idea  of  a  parenchyma,  as  abase  or  generating  ele- 
ment of  all  the  solids,  it  is  an  extremely  vague  one,  and  about 
which  we  have  not  been  able  to  agree.  Haller,*  besides  the 
cellular  tissue  formed  by  the  reunion  of  fibres  and  layers,  and 
which  is  the  most  common  and  extensive,  has  admitted  in  the 
composition  of  the  organs  the  muscular  fibre  and  medullary 
substance.  This  division,  with  some  slight  modifications 
more  or  less  happy,  has  been  since  generally  adopted.  Thus 
Walther  admits  a  cellular  or  membranous  texture,  a  fibrous 
or  vascular  one,  and  a  nervous  one;  Pfaff  a  vascular  structure, 
a  fascicular  and  a  cellular  one;  others  a  cellular,  a  vascular 
and  a  massive  one,  or  one  without  cells  and  vessels.  M.  Chaus- 
sier  has  added  to  the  three  elementary  parts  of  Haller  a  fourth 
fibre  under  the  name  of  albugineous  fibre  :  it  is  the  base  of  the 
ligaments;  M.  Richerand  has  superadded  the  epidermoid  or 
horny  substance.  Among  the  twenty  one  tissues  admitted  by 
Bichat,  there  are  three  which  he  considers  as  generators  of 
the  others :  they  are  the  cellular,  the  vascular  and  the  nerv- 
ous. M.  Meyert  admits,  also  three  elementary  organs:  1st, 
the  cell,  the  vessel  or  the  gland;  2d,  the  irritable  cellular  or 
muscular  fibre;  3d,  the  sensible  fibre  or  the  nerve. 

*  DC.  corporiti  huinuni  fabrica  et  fimdianibus.  Tom.  1.  Lib.  1.  sect.  iii. 
f  Ueber  hutologie,  &c.  Bonn,  1819. 


OF   THE   ORGANS.  87 

§  86.  In  admitting  with  Haller  the  existence  of  three  sim- 
ple organs,  of  three  elementary  tissues,  or  of  three  distinct 
fibres,  distinguished  from  each  other  by  essential  characters, 
viz :  the  cellular  tissue,  the  muscular  fibre,  and  the  medullary 
or  nervous  substance,  we  have  not  even  then  arrived  at  the 
last  point  that  can  be  attained  by  anatomical  analysis.  By  the 
aid  of  the  microscope,  we  see  that  these  simple  organs,  with 
all  their  modifications  and  compounds,  can  be  reduced  to  two 
anatomical  elements.  They  are  formed,  of  an  areolar  permea- 
ble animal  substance  and  of  microscopic  globules,  similar  to 
those  found  in  the  humours.  The  first  substance  alone  forms 
laminae  and  most  commonly  fibres,  differing  from  each  other 
only  in  the  filiform  and  elongated  figure  in  the  first  case,  widen- 
ed in  the  second,  and  which  though  sometimes  separated,  are 
oftener  united :  it  is  from  their  reunion  that  result  the  cells 
or  the  areola3,  &c.  This  first  element,  which  by  itself,  though 
variously  modified,  constitutes  the  greater  part  of  the  organs, 
united  with  the  other,  whose  particles  it  assembles  and  joins, 
forms  the  muscular  fibre  and  the  nervous  substance. 

§  87.  The  organs  also  differ,  one  from  the  other,  in  the  phe- 
nomena they  present  during  life,  and  which  will  soon  be  con- 
sidered. It  will  suffice  here,  to  observe,  that  the  cellular 
substance  is  particularly  remarkable  for  its  continued  contrac- 
tion, which  can  be  augmented  by  impressions  or  irritation ; 
that  the  ligamentous  and  elastic  tissues,  its  two  principal  va- 
rieties are  noted,  the  one  for  its  great  tenacity,  and  the  other 
for  a  great  elasticity;  that  the  muscular  fibre  is, by  its  contrac- 
tion, the  organ  of  all  the  great  motions  and  that  the  nervous 
substance  is  distinguished  from  all  others  by  the  faculty  of 
conducting  all  impressions  to  the  centre,  and  the  action  of  the 
nervous  centre  to  the  muscles,  &c. 

§  88.  The  organs  differing  from  each  other  in  their  con- 
formation, their  texture,  their  physical  properties,  their  che- 
mical composition,  and  during  life  in  the  action  they  produce, 
have  been  divided  into  a  certain  number  of  classes  or  genera. 
These  genera  should  be  determined  from  the  whole  of  the 
characters  taken  together,  and  not  from  the  form  only  j  other- 

1  o 


88  INTRODUCTION. 

wise  we  should  approximate  things  of  widely  different  nature^ 
as  all  the  membranes,  and  we  should  separate  parts,  that  with  the 
exception  of  figure,  are  precisely  alike,  as  the  flat  from  the 
long  bones, the  aponeuroses,  from  the  tendons  or  ligaments,  the 
nerves  from  the  ganglions,  &c.;  the  fibrous  or  fasciculated,  the 
lamellated  or  membranous  forms,  may  belong  to  parts  totally 
different  in  all  other  respects. 

§  89.  The  ancients  divided  the  solid  parts  of  the  body  into 
similar  parts,  and  dissimilar  or  organic  parts.  The  similar  or 
homogeneous  parts  are  those  which  divide  themselves  into 
particles  similar  to  each  other,  as  the  bones,  the  cartilages, 
muscle,  tendons,  &c.  The  dissimilar  parts  are  those  which 
are  formed  by  the  reunion  of  similar  parts,  as  the  hand,  the 
viscera,  the  organs  of  sense,  and  other  compound  organs.  This 
idea  of  Aristotle  reproduced  with  some  new  developments  by 
Goiter,  is  the  origin  and  foundation  of  all  the  divisions  of  the 
organs,  subsequently  established.  The  division  generally 
admitted  in  works  of  anatomy,  of  bones,  muscles,  nerves, 
vessels  and  viscera,  and  some  others,  is  well  known.  But 
these  genera  of  organs,  comprise  compound  parts,  some  of 
them  highly  so  •,  and  on  the  other  hand  these  genera,  and  also 
all  that  of  the  viscera,  include  organs  very  different  from  each 
other — now  this  deprives  us  of  all  the  advantages  of  generali- 
zation. M.  Pinel,  in  France,  and  Carmichael  Smith,*  in 
England,  having  drawn  the  attention  of  anatomists  to  the  fact 
that  the  simple  tissues  which  enter  into  the  composition  of 
dissimilar  or  compound  parts  could  be  separately  diseased, 
and  particularly,  inflamed,  and  that  their  inflammation  was  the 
same,  whatever  was  the  compound  organ  of  which  they  made 
a  part,  it  soon  led  to  a  more  complete  anatomical  analysis, 
than  had  hitherto  been  made,  especially  as  regarded  the  vis- 
cera. Bichatt  developing  this  prolific  idea — one  worthy  of 
his  genius — has  arranged  all  the  simple  organs  under  the  name 
of  tissues  or  of  systems,  in  twenty  one  genera.  M.  Chaussier 

*  On  inflammation,  in  Medical  Communications,  Vol.  II. 
f  Anat.  generate,  appliquee  a  la  physiologic  et  a  la  medecine  par  Xav» 
Bichat. 


OF   THE   ORGANS.  89 

has  distinguished  the  twelve  genera  of  organs,  the  last  com- 
prising the  viscera  or  compound  organs.  Since  then,  several 
authors,  adopting  their  leading  principles,  have  modified  the 
classifications  of  the  two  anatomists.* 

§  90.  In  the  midst  of  this  variety,  the  following  is  a  classi- 
fication or  division  of  the  organs  in  genera,  drawn  from  the 
ensemble  of  their  anatomical,  chemical,  physiological  and 
pathological  characters. 

The  cellular  tissue,  the  principal  and  general  element  of  or- 
ganization, should  be  first;  it  exists  in  the  whole  organic  king- 
dom, enters  into  all  the  organs  and  constitutes  the  base  of  all 
organization. 

This  tissue,  somewhat  modified  in  its  consistence,  form,  and 
the  proportion  of  earthy  matter  it  contains,  forms  several  other 
genera  of  organs. 

Arranged  in  membranes,  closed  on  all  sides,  in  whose 
thickness  it  has  more  firmness  and  less  permeability,  it  con- 
stitutes the  serous  and  synovial  systems. 

It  forms  the  tegumentary  tissue,  which  embraces  the  skin 
and  mucous  membranes,  as  well  as  the  follicles  of  these 
two  kinds  of  membranes,  and  the  organs  producing,  hairs, 
teeth,  &c. 

It  is  also  the  same  with  the  elastic  tissue,  which  is  the  base 
of  the  vascular  system,  which  comprises  the  arteries,  the  veins 
and  the  lymphatic  vessels,  and  which  stilLbelongsto  the  same 
order,  in  approximating  to  the  muscular  tissue. 

The  glandular  system,  which  is  formed  by  the  union  of  the 
tegumentary  and  vascular  systems,  is  also  of  the  same  order 
of  organs. 

The  ligamentous  system  comprising  very  tenacious  and  re- 
sisting organs,  also  results  from  a  modification  of  the  cellular 
tissue. 

*  See  almost  all  the  works  on  anatomy  and  physiology  since  1801,  and  par- 
ticularly J.  F.  Meek  el's  Handbuch  der  menschlichcn  anatomic, — Erster  Band. 
JLllgcmeinc  anatomic.  Halle  and  Berlin,  1815. — T.  Gordon.  Ji  system  of  hu- 
man Anatomy,  Vol.  I.  Edinb.  1815.  P.  Mascagni.  Prodromo  della  grande 
anatomia.  Fircnze,  1819. — C.  Meyer. — Opuse.  cit. 


90  INTRODUCTION. 

Finally,  the  cartilaginous  and  bony  systems  belong  to  the 
cellular  tissue,  and  owe  their  solidity  to  its  condensation  and 
the  great  quantity  of  earthy  salts  that.substance  contains. 

A  second  order  of  organs  is  formed,  essentially,  by  the 
muscular  fibre:  this  is,  the  muscles,  whether  belonging  to  the 
bones,  to  the  external  and  internal  teguments,  to  the  senses, 
or  to  the  heart. 

The  nerves  and  the  central  nervous  masses,  constitute  the 
third  and  last  order  of  organs,  essentially  formed  by  the  nerv- 
ous substance. 

It  will  be  seen  that  this  classification  reposes  on  the  basis 
indicated  by  Haller,  and  which  truly  exist  in  nature. 

§  91.  The  order  in  which  the  genera  of  organs  should  be 
arranged,  may  be  founded  on  various  bases:  if  we  paid  any 
attention  to  the  universality,  more  or  less  great,  of  the  organs 
in  the  series  of  animals,  the  cellular  tissue  should  be  placed 
first;  after  it  would  come,  the  tegumentary  organs;  then  the 
muscles  and  nerves,  the  vessels,  the  glands ;  the  cartilaginous 
and  bony,  the  ligamentous  and  serous  tissues  would  be  placed 
last  as  peculiar  to  the  vertebrata.  Another  order  would  be 
followed  if  we  were  first  to  class  the  kinds  of  organs  that  be- 
long to  the  common  or  vegetative  functions,  and  next,  those 
which  form  the  apparatus  of  functions  proper  to  animals. 
Another  order  would  be  established,  if,  like  Bichat  we  were 
first  to  arrange  the  general  systems,  as  the  cellular  tissue,  the 
vessels  and  the  nervesj  and  then  the  particular  systems.  It  is 
a  matter  of  but  little  importance,  although  it  is  preferable  to 
arrange  the  organs  from  their  analogies,  as  we  have  done. 

§  92.  Several  physiologists,  still  place  the  epidermic,  or 
horny  substance,  among  the  primitive  fibres;  but  this  almost 
inorganic  substance,  produced  by  excretion  can  not  be  consi- 
dered as  an  anatomical  element.  The  characters  assigned  to 
it  are  the  following;  it  contains  no  distinct  cellulosity;  ma- 
ceration reduces  it  into  a  sort  of  mucilage;  chemistry  proves 
that  it  contains  albumen,  according  to  some,  and  mucus  accord- 
ing to  others,  not  very  different  things,  since  mucus  appears 
to  be  albumen  united  to  soda.  This  substance  is  that  which 


OP   THE   ORGANS.  91 

constitutes  the  epidermis,  the  nails,  hairs,  and  all  the  horny 
parts  of  animals.  Although  a  slight  difference  appears  to  exist 
between  the  horny  and  epidermic  matters,  it  is  not  sufficiently 
great,  to  prevent  us  from  referring  them  to  the  same  sub- 
stance. M.  Meyer,  who  has  recently  given  a  new  classifica- 
tion of  the  solids  of  the  human  body,  looks  upon  the  mem- 
brane of  the  tympanum,  the  cornea  and  crystalline,  as  being 
formed  of  this  substance,  which  he  calls  the  scaly,  or  lamel- 
lated  tissue;  but  this  approximation  has  no  foundation,  parti- 
cularly the  first.  The  epidermic  substances  are  remarkable 
for  the  facility  and  promptitude  of  their  reproduction. 

§  93.  The  names  of  fibre,  tissue,  organ,  &c.,  generally 
designate  the  organic  solids.  The  meaning  attached  to  them 
should  be  more  particularly  specified.  We  call  tissue,  every 
part  that  is  distinct  from  another  by  its  texture.  The  tissue  dif- 
fers from  the  fibre,  only  inasmuch  as  the  latter  is  the  finer  and 
composing  part  of  it.  A  tissue  may  be  formed  by  fibres  that 
are  similar  or  dissimilar.  An  organ,  generally,  results  from 
the  reunion  of  several  tissues.  These  distinctions  however, 
are  not  absolute:  thus  the  cellular  tissue  represents  at  the  same 
time,  a  particular  fibre,  a  tissue  formed  by  that  fibre  and  an 
important  organ  of  the  animal  economy.  Generally  speaking, 
the  fibre  is  the  element,  the  tissue  indicates  the  arrangement 
of  parts  and  the  organ,  a  compound  part  which  has  a  peculiar 
action.  Almost  all  the  solids  are  formed  by  the  cellular  fibre 
and  its  two  modifications;  some  tissues  have,  for  a  base,  the 
muscular  and  nervous  fibres ;  one  alone,  which  is  the  tegu- 
mentary  tissue,  contains  the  epidermic  substance.  The  organs 
are,  almost  always,  parts  more  or  less  compound;  thus  in  a 
muscle  we  find  the  muscular  fibre,  the  cellular  tissue  which 
surrounds  it,  and,  at  the  extremity,  the  tendon  to  which  it  is 
attached;  in  the  same  way  in  a  nerve,  there  is  a  soft  and  me- 
dullary substance  in  the  centre,  and  externally  a  particular 
membrane  called  the  neuralima.  Certain  parts,  such  as  the 
stomach,  the  eye,  are  still  more  compound.  Generally,  every 
organ  or  acting  part  contains  cellular  tissue,  vessels  and  nerves. 
The  cellular  tissue  is  the  most  extended:  there  is  no  one  part 
where  it  is  not  to  be  found  under  one  form  or  another.  After 


92  INTRODUCTION. 

the  tissue  come  the  vessels — with  but  very  few  exceptions, 
we  every  where  find  vessels  of  different  kinds,  white  or  red. 
The  nerves  are  less  abundant  than  the  vessels,  and  of  course, 
less  so  than  the  cellular  tissue:  the  greater  number  of  the  or- 
gans, however,  are  provided  with  them.  We  may,  then, 
regard  the  organs,  as  parts  into  whose  composition  the  cellu- 
lar tissue  constantly  enters,  vessels  almost  alwa}rs,  and  nerv- 
ous tissue  generally. 

The  viscera  or  splanchnic  organs  take  their  name  from  the 
importance  of  their  offices.  They  are  the  organs,  the  most 
essential  to  life;  those  by  which  we  live ;  they  are  of  all  the 
organs  the  most  compound;  they  are  situated  in  the  cavities 
of  the  body,  called  splanchnic.  They  comprehend  the  organs 
of  digestion,  of  generation,  and  of  the  urinary  secretion,  con- 
tained in  the  abdomen;  of  those  of  circulation  and  respiration, 
which  are  contained  in  the  thorax,  and  the  sensorial  and  nerv- 
ous organs,  in  the  cranium  and  vertebral  canal.  It  is  particularly 
to  the  thoracic  and  abdominal  organs,  and  to  the  latter  espe- 
cially, that  is  given  the  name  of  viscera. 

§  94.  We  understand  by  system  or  genus,  a  union  of  parts 
of  similar  texture,  such  as  the  bones,  the  muscles,  the  liga- 
ments, &c.:  this  corresponds  to  the  similar  parts  of  the  an- 
cients. Parts  such  as  the  skin,  and  the  cellular  tissue  extended 
over  the  whole  body,  and  thereby  presenting  regions,  and 
divisions,  but  not  like  the  preceeding  ones,  distinct  portions, 
have  also  been  thus  designated.  Bichat,  particularly  used  the 
word,  system,  in  this  acceptation.  The  study  of  the  genera 
of  organs,  or  of  the  systems  constitute  the  object  of  general 
anatomy,  which,  in  this  way,  embraces  every  thing  that  simi- 
lar parts  have  in  common,  and  at  the  same  time  whatever  the 
generally  extended  tissues  possess  in  common  in  the  different 
regions. 

§  95.  The  apparatuses  are  ensembles  of  organs;  sometimes 
very  distinct  by  their  formation,  situation,  structure  and  even 
by  their  particular  action,  but  which  concur  in  one  common 
end,  which  is  one  of  the  functions  of  life.  It  is  an  error  to 
confound  this  reunion  of  parts  with  that  which  constitutes  a 
system  or  a  genus  of  organs.  The  classification  of  the  appa- 


OP   THE    ORGANS.  93 

rajuses  rests  entirely  on  the  consideration  of  the  functions, 
while  that  of  the  systems  or  the  genera  depends  upon  the  re- 
semblance of  the  parts  with  each  other.  We  have  seen  as 
above  the  enumeration  of  the  genera  of  the  organs;  we  shall 
now  show  how  the  organs  are  united  in  apparatuses  of  func- 
tions. 

The  bones  and  their  dependencies,  viz:  the  periosteum, the 
medulla,  the  greater  part  of  the  cartilages,  the  ligaments,  the 
synovial  capsules,  constitute  &  first  apparatus  of  organs  which 
determine  the  form  of  the  body,  which  serve  as  supports  for 
all  its  parts,  and  particularly  as  an  envelope  to  the  nervous 
centres,  and  which,  by  the  mobility  of  the  articulations,  re- 
ceive and  communicate  the  movements  determined  by  the 
muscles. 

The  muscles,  the  tendons,  the  aponeuroses,  bursse  mucosae, 
form  the  apparatus  of  motion. 

The  cartilages  and  the  muscles  of  the  larynx,  and  various 
other  parts  form  that  of  phonatiorf,  or  of  the  voice. 

The  skin,  the  other  senses,  and  the  muscles  which  move 
them,  &c.  form  the  apparatus  of  the  sensations. 

The  nervous  centres  and  the  nerves  form  that  of  innerva- 
tion. 

The  alimentary  canal,  from  the  mouth  to  the  anus,  with  all 
its  numerous  dependancies,  constitute  that  of  digestion. 

The  heart  and  the  vessels,  that  of  circulation. 

The  lungs,  that  of  respiration. 

The  glands,  the  follicles  and  the  perspiratory  surfaces,  form 
the  apparatus  of  the  secretions;  but  the  greater  part  of  these 
organs  serving,  for  other  functions,  are  comprehended  in  their 
apparatuses.  There  remains  but  the  urinary  secretions,  whose 
organs  alone  constitute  an  apparatus. 

The  genital  organs  constitute  a  different  apparatus  in  each 
sex. 

Finally,  the  ovum,  and  the  foetus  it  encloses,  form  a  last  group 
or  apparatus  of  organs. 


94  INTRODUCTION. 

OP   THE   ORGANISM. 

§  96.  The  human  body,  during  life,  presents  many  pheno- 
mena of  different  kinds.  In  it,  as  in  all  bodies,  mechanical  and 
chemical  actions  contantly  occur;  but  they  are  modified  by 
those  of  life.  There  is,  in  fact,  in  the  human  body,  as  in  all 
such  as  are  organized  and  living,  the  essential  phenomena  of 
life,  viz:  nutrition  and  generation,  organic  actions,  whose  ex- 
ercise is  subordinate  to  other  actions  proper  to  animals,  viz: 
the  muscular  movements  and  the  sensations,  subordinate 
themselves  to  the  innervation.  These  animal  actions  are  di- 
rected by  the  functions  of  a  superior  order — those  of  intelli- 
gence. 

Besides  this  remarkable  order  of  subordination  in  the  phe- 
nomena of  life,  there  exists  between  them  a  connexion,  so 
that  the  functions  of  an  inferior  kind,  also  hold  in  dependance, 
those  of  a  more  elevated  one,  and  that  all  the  functions  are  in 
such  a  state  of  mutual  dependance,  that  the  phenomena  of  life 
may  be  compared  to  a  circle,  which  once  traced,  has  neither 
beginning  nor  end.  As  has  been  already  stated,  it  is  this  en- 
semble of  organic  actions  that  is  called  organism  or  life. 

§  97.  We  call  function,*  the  action  of  an  organ  or  of  an 
apparatus  of  organs  having  one  common  end.  These  functions 
have  been  classed  or  distributed  in  several  genera;  not  that 
these  divisions  are  perfectly  exact,  or  that  they  are  very  useful 
as  aids  to  the  memory,  since  the  objects  classed  are  by  no 
means  numerous;  but  because  in  their  study  it  is  necessary  to 
follow  some  order  or  other,  and  it  is  better  to  follow  a  natural, 
than  an  arbitrary  one.  The  divisions  of  the  ancients,  adopted 
with  some  slight  modifications  by  Haller,Blumenbach,  Chaus- 
sier,  and  some  other  moderns,  consist  in  the  arrangement  of 
the  functions  in  four  classes :  the  vital,  animal,  natural  or  nu- 
tritive, and  the  genital  functions.  Another  division,  also 
taken  from  the  ancients,  since  the  first  idea  of  it,  is  to  be 
found  in  Aristotle,  which  has  been  pointed  out  by  Bufibn, 
Grimaud,  &c.,  and  which  has  been  adopted  and  developed  by 

*  See  Chaussier,  Table  synoptique  des  f auctions. 


OF    THE    ORGANISM.  95 

JBichal  and  Richerand,  consists  in  classing  the  functions  in 
those  of  the  species  and  in  those  of  the  individual,  and  these 
latter,  in  functions  of  relations  or  animal  functions,  and  in 
those  of  nutrition  or  organic  functions, 

§  98.  The  following  is  a  very  natural  order,  in  which  the 
functions  may  be  classed.  Some  are  common  to  all  organized 
bodies,  vegetable  as  well  as  animal;  if  not  by  all  their  actions, 
and  all  their  organs,  at  least  by  the  result.  These  are  the 
common,  organic,  or  vegetative  functions.  1st,  nutrition, 
which  comprehends,  digestion,  absorption,  circulation,  respi- 
ration, and  the  secretions,  and  whose  definite  result  is  the  per- 
petuating the  individual  in  its  form,  composition,  and  tempera- 
ture; 2d,  generation,  which  comprehends  the  formation  of 
germs,  that  of  the  sperm,  fecundation,  and  the  development  of 
the  fecundated  germ,  and  whose  result  is  the  perpetuity  of  the 
species,  or  of  a  succession  of  similar  individuals.  The  other 
functions  are  proper  to  animals;  they  are:  3d,  the  muscular  ac- 
tion whose  results  are  locomotion,  gesture,  and  voice,  and 
moreover,  the  muscular  movements  necessary  to  the  execu- 
tion of  the  two  preceding  functions;  4th,  the  sensations,  and 
5th,  the  nervous  action  or  innervation.  There  is  yet  another 
order  of  functions,  belonging  exclusively  to  man,  viz.  the  in- 
tellectual, which,  in  other  animals,  that  most  resemble  him, 
exists  only  in  appearance.  Finally,  man  not  only  exercises 
his  individual  functions,  and  those  of  generation,  but,  living  in 
society,  he  exercises  collective  actions,  whose  observation  and 
bearing  are  foreign  to  physiology  and  medicine. 

§  99.  While  bodies  are  at  rest,  we  perceive  nothing  but  the 
qualities  by  which  they  strike  our  senses.  While  in  action  or 
motion,  we  can  still  only  perceive  phenomena,  or  changes  per- 
ceptible to  our  senses.  Among  these  qualities  and  phenomena, 
some  are  common  to  all  bodies,  others  are  peculiar  to  organized 
and  living  ones;  these  last  have  their  peculiar  qualities  and 
phenomena,  in  a  word,  their  properties.  Properties,  are  in 
fact,  nothing  else  than  sensible  qualities  and  phenomena.  When 
the  latter  reproduce  themselves  in  an  order,  all  of  whose  con- 
ditions we  can  determine,  we  know  the  law  of  such  pheno- 
mena, that  is  to  say,  the  rule  they  follow,  and  to  which,  it  ap- 
14 


96  INTRODUCTION. 

pears  to  us  they  are  subject:  this  law  when  it  is  general  is  call- 
ed theory.  Beyond  this,  we  know  nothing.  But  we  admit 
in  general,  that  matter  is  inert,  and  every  time  we  see  it  in 
motion,  we  suppose  a  cause  of  motion  that  makes  it  act,  and 
which  we  call  force.  Thus,  organic  matter  being  in  action 
during  the  entire  life  of  organic  bodies,  we  say  that  life  is 
caused  by  a  vital  force.* 

This  force  has  been  considered  as  a  different  substance  from 
that  of  the  organs,  and  of  which  these  latter  were  the  instru- 
ments, at  one  time  it  has  been  considered  rational,  at  another 
the  reverse.  It  has  also  been  regarded  as  a  faculty  proper  to 
matter;  either  to  organic  solid  matter,  or  to  that  which  is  fluid. 
It  has  also  been  thought  to  be  the  result  of  organization,  i.  e. 
of  the  assemblage  of  all  the  solid  and  liquid  parts  of  an  or- 
ganized body,  etc. 

It  would,  doubtless,  have  been  better  in  a  physical  science, 
like  that  of  the  organization  of  life,  had  we  confined  ourselves 
to  the  observation  of  bodies  and  facts. 

§  100.  The  organic  or  vital  phenomena,  differing  from  each 
other,  the  vital  or  organic  forces  that  have  been  admitted,  must 
consequently  be  of  several  kinds. 

There  are  phenomena  of  organic  formation,  such  as  those  of 
nutrition,  generation,  the  reparation  of  lesions,  reproduction, 
etc.  A  force  or  power  of  formation,  has  consequently  been 
admitted  under  the  name  of  plastic  force,  formative  force,t  vi- 
tal affinity,  it  is  common  to  all  organic  bodies,  and  to  all  their 
parts. 

§  101.  The  solids  of  organized  bodies,  and  particularly  of 
animals,  receive  impressions  from  various  agents,  that  are  im- 
mediately followed  by  movements  more  or  less  appreciable: 
these  are  called  movements  of  irritation,  and  the  force  or  the 
cause  to  which  they  are  attributed,  irritability.^  All  animal 
parts  are  more  or  less  susceptible  of  it.  We  notice  three  prin- 
cipal varieties  of  it.  In  the  cellular  tissue  where  it  is  weak,  it 

*  See  Reil.    Von  der  kbenskraft,  in  archiv-  furv  die  physiologic.  B.  I.  Halle, 
1795. — Chaussier.   Table  synoptique  de  la  force  vitale,  etc. 

f  See  Blumenbach.    Uber  dm  Bildnngstricb.   Getting-. 

*  See  Gautier.  de  irritabilitatis  notione,  natura  et  morbis.  Halx,  1793. 


OP  THE  ORGANISM.  97 

is  called  tonicity;  in  the  vessels  where  it  is  more  marked,  it  is 
called  vascular  contractility,  and  in  the  muscles  where  it  is 
greatest,  muscular  irritability  or  myotility. 

It  is  remarkable  that  all  these  movements  consist  in  contrac- 
tions. It  has  been  thought,  however,  that  certain  movements 
depended  upon  an  expansion,  an  elongation,  or  a  turgescence,* 
this  appears  to  have  been  caused  by  a  want  of  close  observa- 
tion. 

§  102.  In  man,  and  in  those  animals  that  have  distinct  nerves 
and  a  nervous  centre,  the  impressions  received  are  transmitted 
by  the  nerves,  and  felt  at  the  centre,  and  the  centres  transmit 
their  action  to  the  muscles  by  the  nerves.  The  cause  to  which 
these  phenomena  are  attributed,  is  called  the  nervous  force,  in 
one  word,  sensibility.  Among  the  sensations,  some  are  ex- 
tremely obscure,  and  but  vaguely  perceived,  t  They  are  pretty 
nearly  every  where  extended,  particularly  in  the  mucous  mem- 
branes. In  a  state  of  health,  they  constitute  a  general  senti- 
ment of  well  being;  when  they  are  increased  by  certain  causes, 
they  give  rise  to  a  morbid  sensation  called  pain.  There  is  no 
part  which  may  not  become  the  seat  of  this  morbid  sensibility. 
The  other  sensations  are  distinct,  and  some  of  them  altogether 
special. 

As  to  the  nervous  action  on  the  muscles,  it  directs  their  ir- 
ritability; its  power  is  also  extended  to  the  vessels,  particularly 
to  the  smallest. 

Moral  and  intellectual  acts,  differ  so  widely  from  organic 
phenomena,  that  it  is  impossible  they  can  depend  on  the  same 
cause;  they  would  in  this  case  be  necessary  and  blind,  instead 
of  being  enlightened  and  free.  Physiology,  which  on  the  one 
side  is  met  by  natural  philosophy,  here  encounters  moral  phi- 
losophy or  metaphysics. 

§  103.  The  functions  are  not  exercised,  or  if  you  will,  the 
vital  forces  do  not  enter  into  action  spontaneously,  but  by 
means  of  stimulants  or  exciting  causes;  whether  they  be  the 
bodies  which  act  on  the  external  and  internal  surfaces  of  the 
body,  or  the  blood  which  penetrates  all  its  parts.  In  relation 

*  See  Hebenstreit,  Jf  Turgore  v'ltati.   Lipsix,  1795. 
f  See  Hubner,  de  Coenxsthesi/  Hal*.   1794. 


98  INTRODUCTION. 

to  their  effects,  stimuli  differ  materially  from  each  other.  As 
to  the  subjects  on  which  they  act,  their  difference  is  not  less, 
and  depends  on  age,  sex,  and  above  all,  on  the  diversity  of  the 
organs,  which  feel  more  or  less  the  action  of  the  same  agent. 
Every  thing  being  united  in  the  organization,  the  action  of 
an  organ  is  not  isolated:  those  which  have  centres,  influence 
all  that  are  subordinate  to  them.  Others  perform  their  func- 
tions by  association.  Some  of  them  to  supply  the  want  of  it, 
execute  the  action  which  is  interrupted  in  another.  There  is 
not  a  single  one  of  them,  which,  being  extraordinarily  excited, 
by  an  appropriate  stimulus,  does  not  influence  more  or  less  the 
whole  organism. 

OF  THE  DEVELOPMENT  AND    DIFFERENCES    OF  THE  ORGANIZA- 
TION. 

§  104.  Each  organ,  each  action,  and  consequently,  the  entire 
organism,  presents  stadia  or  degrees  of  development  and  per- 
fection. A  first  period  is  that  of  youth,  of  a  successive  growth 
and  perfection,  or  a  second,  very  short  one,  is  that  wherein 
the  organization  remains  in  a  state  of  maturity;  a  third  is  that 
in  which  the  organization  is  progressively  altered,  and  natural- 
ly arrives  at  death  and  destruction. 

-  §  105.  It  is  in  the  beginning  of  life,  that  the  similitude  be- 
tween the  lateral  parts  is  the  greatest.  The  heart  is  then  ver- 
tical and  median,  the  lobes  of  the  liver  nearly  equal,  the 
stomach  vertical,  etc.  The  upper  and  lower  members  are  ex- 
actly alike,  at  the  moment  they  make  their  appearance,  and  for 
a  short  time  after.  The  genital  organs  of  both  sexes  are  at  first 
similar.  It  is  also  in  the  commencement  of  life  that  animals 
bear  the  strongest  resemblance  to  each  other.  The  relative 
size  of  the  parts  changes  with  age:  thus  the  nervous  system, 
the  senses,  the  heart,  the  liver  the  kidneys  etc,  are  at  first 
large,  in  comparison  with  the  rest  of  the  body,  while  on  the 
contrary,  the  intestine,  the  spleen,  genital  organs,  lungs,  mem- 
bers, etc,  are  very  small  as  regards  the  rest  of  the  body,  and 
the  other  organs.  This  added  to  the  fact,  that  certain  parts 
disappear,  or  greatly  diminish  with  age,  constitutes  a  species 


DEVELOPMENT,  ETC.  OF   ORGANIZATION.  99 

of  metamorphosis;  thus  the  membranes  of  the  ovum  and  the 
placenta,  the  pupillary  membrane,  the  milk  teeth  cease  to  ex- 
ist, and  the  surrenal  capsules  and  the  thymus  gland,  greatly 
diminish,  and  finally,  almost  totally  disappear. 

§  106.  The  organs  and  humours  are  not  always  in  the  same 
proportion.  In  the  beginning  the  embryo  is  nothing  but  a 
nearly  liquid  molecule ;  in  time  the  proportion  of  solids  in- 
creases and  continues  to  augment  till  the  end.  The  colour  is 
also  gradually  developed;  at  first  all  the  parts  are  white,  the 
colouring  of  the  blood  and  other  parts  takes  place,  by  degrees. 
There  is  at  first  no  determined  texture  in  the  organs:  there  is 
even  no  globules  in  the  beginning,  while  at  a  later  period,  the 
whole  mass  of  the  body  appears,  globular,  or  granulated,  after 
which  fibres,  lamina  and  vessels  become  distinct.  All  the 
organs  are  not  developed  at  one  time.  Even  those  of  the 
same  genus  or  system  are  not  all  formed  together.  The  ex- 
ternal form  or  configuration  is  drawn  before  the  consistence, 
texture  and  composition  are  fixed;  for,  as  we  see  in  the  fruit 
of  the  almond  which  has  already  its  form,  and  is  as  yet  a  mere 
glairy  liquid  which  will  successively  acquire  the  consistence, 
texure  and  composition  proper  to  it,  so  the  nervous  and  bony 
systems  already  have  partly  their  form  while  yet  liquid.  The 
cellular  tissue;  and  the  vessels  permeable  by  liquids,  diminish 
from  the  beginning  to  the  end  of  life;  it  is,  above  all,  this 
change  which  continues  after  the  end  of  the  growth,  that  essen- 
tially appears  to  constitute  the  period  of  the  deterioration  of 
the  organism  and  of  old  age. 

§  107.  The  organs  are  formed  by  separate  parts  that  after- 
wards unite;  thus  the  nervous  medulla  is  at  first  a  double 
cord  ;  the  intestine  and  the  cavity  of  the  trunk,  at  first  open 
in  front,  afterwards  close — it  is  also  the  same  with  the  spinal 
canal.  The  vessels,  at  first,  are  isolated  vesicles  which  stretch 
and  communicate  in  the  mass  of  the  body :  the  kidneys,  at  first 
multiple,  coalesce  and  adhere;  the  bones  which  in  the  carti- 
lagenious  state,  lengthen  themselves  by  a  species  of  vegeta- 
tion, afterwards  become  ossified  in  separate  parts  which  then 
unite,  &c.  Traces  of  this  formation,  remain  in  certain  places, 
stronger  in  some,  weaker  in  others;  thus  the  raphe  of  the  skin, 


100  INTRODUCTION. 

the  middle  suture  of  the  os  frontis,  the  median  line  of  the 
uterus,  &c.  are  sufficiently  apparent  marks  of  a  reunion  of  the 
two  halves;  on  the  contrary,  in  the  superior  portion  of  the  ster- 
num, in  the  body  of  the  vertebra,  these  traces,  are,  generally, 
completely  effaced. 

§  108.  All  the  phases  through  which  the  human  organism 
passes,  correspond  with  permanent  states  or  conditions  in  the 
animal  kingdom.  We  could  here  accumulate  the  proofs  of 
this  important  proposition  by  drawing  a  parallel  between  the 
human  foetus  in  its  various  stages  of  development  and  the  de- 
grees of  organization  of  the  animal  scale.  Some  few  exam- 
ples, however,  will  suffice.  The  embryo  is  at  first  a  mere  bud 
or  germ,  placed  on  a  vesicle,  such,  are  some  of  the  most  sim- 
ple worms.  At  a  more  advanced  epoch,  it  is  a  little  vermiform 
body  without  distinct  members  or  head;  this  is  the  case  with 
the  annelides;  still  later,  the  members  are  equal  and  the  tail 
protrudes:  such  is  the  fact  with  respect  to  the  greater  portion 
of  quadrupeds.  In  the  nervous  system,  we  first  see  the  nerves 
with  their  ganglions:  such  is  the  case  with  all  the  inverte- 
brata  provided  with  nerves;  at  a  later  period  we  can  distin- 
guish the  vertebral  and  cranial  medulla,  the  tubercles  of  the 
latter,  and  as  yet  only  the  rudiments  of  a  cerebrum  and  cere- 
bellum:  this  is  the  case  with  fishes  and  reptiles;  still  later 
these  last  parts  increase  much  more  than  the  tubercles  and  the 
encephalon  is  successively  that  of  birds  and  the  mammalia, 
until,  finally,  by  the  predominance  of  the  cerebral  and  cere- 
bellous  lobes,  it  becomes  that  of  man  himself.  We  should  see 
in  following  the  development  of  the  bones,  that  they  are  at 
first  mucilaginous,  then  cartilaginous,  afterwards  bony  and  in 
this  state,  separated  in  pieces,  which  are  afterwards  welded 
together;  in  comparing  this  development  with  the  state  of 
the  bony  system  in  the  lamprey,  in  the  cartilaginous  fishes 
and  in  the  oviparous  vertebrata  in  general,  we  should  have 
another  proof  of  the  proposition  advanced.  It  would  be  the 
same  if  we  were  to  pass  in  review  all  the  genera  and  all  the  ap- 
paratuses of  organs. 

§  109.  Man  is  distinguished  from  all  other  animals  by  the 
great  rapidity  with  which  he  passes  through  the  first  epochs 


DEVELOPMENT,  ETC.   OF  ORGANIZATION.  101 

of  his  formation  or  of  his  development;  consequently,  it  is 
also  difficult  to  perceive  in  him  these  first  changes.  The 
comparison  of  man  with  animals,  and  of  man  with  himself  at 
different  ages,  is  a  point  of  comparative  anatomy,  which  al- 
ready rich  in  a  great  number  of  facts,  recommends  itself  by 
its  importance  to  the  observation  of  the  accoucheur.  •, 

§  110.  As  may  easily  be  imagined,  the  organic  phenomena 
follow  the  successive  development  of  the  organs.  In  the 
embryo,  there  is  only  an  almost  direct  absorption  and  assimu- 
lation  of  the  nutritive  matter;  afterwards  the  vessels  become 
apparent,  and  it  is  the  circulation  which  then,  every  where  dis- 
tributes the  materials  of  nutrition;  the  secretions  then  begin 
to  form,  and  the  blood  of  the  foetus,  brought  into  contact  with 
that  of  the  mother  through  the  medium  of  the  placenta,  de- 
rives from  it  a  kind  of  branchial  respiration.  At  birth,  atmos- 
pheric respiration  and  digestion  are  added  to  the  other  nutri- 
tive functions,  and  the  animal  functions  enter  into  exercise; 
and  here,  as  in  the  whole  animal  kingdom,  we  see  the  organs 
and  their  functions  the  last  developed,  hold  all  the  rest  in  a 
state  of  dependence,  and  life  to  result  from  the  connexion  of 
organic  actions  with  each  other. 

§  111.  The  organization  of  man  presents  differences  in  the 
sexes:*  besides  those  that  exist  in  the  organs  of  generation, 
there  are  others  in  the  general  form  of  the  body  and  in  the 
proportion  of  its  parts.  Man  is  generally  larger  than  woman; 
the  total  weight  of  his  body  is  about  one  third  greater.  The 
contour  is  more  rounded  in  woman,  bolder  and  more  salient 
in  man;  the  trunk  of  woman  is  shorter,  and  the  inferior  ex- 
tremities longer,  so  that  the  middle  of  her  body  is  lower  in 
her,  than  in  man — the  abdomen,  and  the  pelvis  particularly, 
are  larger  in  proportion  than  the  shoulders  and  chest,  which 
is  short,  and  tapering.  The  organs  contained  in  the  abdomen, 
are  larger,  and  those  of  the  breast  and  neck  smaller,  in  pro- 
portion to  the  rest  of  the  body,  in  woman  than  in  man;  the 
bones  and  the  muscles  are  less  developed,  the  adipose  tissue 

*  Sec  J.  F.  Ackerman,  de  discrimine  sexuum  prscfer  gemtalia.  Mogunt, 
1787. — Ejusd.  historia  etichnogr.  infantis  androgyni—Jente,  1805. 


102  INTRODUCTION. 

more  so;  the  general  texture  of  the  parts  is  softer  and  more 
lax;  the  hairs  weaker  and  less  numerous.  As  to  the  genital 
organs,  the  very  great  differences  they  present,  do  not  destroy 
their  essential  analogy.  The  external  characters  of  the  sexes 
we  have  just  indicated,  appear  to  depend  upon  the  existence 
and  action  of  the  ovary  in  woman  and  of  the  testicle  in  man. 
In  the  embryo,  where  the  sex  is  doubtful,  there  are  no  exter- 
nal appreciable  differences;  in  the  foetus  and  infant  they  begin 
to  show  themselves  in  proportion  as  the  genital  organs  are 
developed:  in  puberty  the  sexual  characters  are  most  perfect, 
in  old  age  they  become  less  so.  The  want  of  a  complete  de- 
velopment of  the  ovaries  or  testicles,  their  changes  by  disease, 
and  their  ablation,  likewise  prevent  the  general  differences  of 
the  sexes  from  establishing  themselves,  or  efface  them  more 
or  less  completely.  The  causes  of  the  difference  between  the 
sexes  has  been  sought  for  in  a  supposed  predominance  of  the 
coagulating  principal,  or  of  oxygen  in  the  male  and  of  the  nu- 
tritive matter  in  the  female. 

§  112.  The  human  species  presents  differences  of  organiza- 
tion, hereditary  in  the  races  or  varieties,*  scattered  over  the 
globe,  and  that  may  be  considered  five  in  number,  and  of 
which  there  are  three  principal  ones,  viz:  the  Caucasian,  the 
Mongol  and  the  Ethiopian,  and  the  Malay  and  American 
races. 

§  113.  The  Caucasian,  to  which  we  belong,  is  remarkable 
for  the  beauty  of  the  form  and  the  proportions  of  the  head,  in 
which  the  cranium  is  much  larger  than  the  face;  a  fact  of 
which  any  one  will  be  convinced  by  simple  inspection,  as  well 
as  by  the  application  of  cephalometers.  The  cranium  is  high 
and  rounded,  the  face  is  oval  and  its  parts  but  slightly  salient. 
The  colour  of  the  skin  is  generally  white  and  rosy;  that  of 
the  eyes  blue  or  brown,  that  of  the  hair,  which  is  generally 
abundant,  fine  and  long,  varies  from  white  to  black. 

The  Caucasian  is  peculiarly  remarkable  for  the  development 
of  his  intelligence,  for  civilization  and  the  culture  of  philoso- 

*  See  Blumenbach,  op,  cit- — Lawrence,  op.  cit. 


DEVELOPMENT  ETC.  OF  ORGANIZATION.  103 

phy,  the  sciences  and  the  arts.  The  coloured  races  on  the 
contrary  have  the  senses  in  greater  perfection. 

§  114.  The  mongol  is  recognised  by  the  strength  of  the 
trunk,  the  smallness  of  the  members,  the  almost  square  form 
of  the  head,  and  the  obliquity  of  the  forehead,  by  the  breadth 
and  flattening  of  the  face,  the  projection  of  the  cheek  bones, 
and  by  the  separation,  narrowness,  and  obliquity  of  the  eyes; 
the  skin  is  olive;  the  hair  is  straight,  black  and  short;  the  beard 
scanty,  and  sometimes  totally  wanting. 

§  115.  The  negro  has  the  trunk  slender,  particularly  at  the 
loins  and  pelvis;  the  superior  members  are  long,  particularly 
the  fore-arm;  the  hands  are  small,  the  feet  large  and  flattened; 
the  knee  and  foot  are  turned  outwards;  the  head  is  narrow  and 
elongated;  the  inferior  part  of  the  face  projects;  the  nose  is 
flattened ;  the  anterior  teeth  are  oblique,  and  the  lips  salient ; 
the  skin,  the  iris  and  the  hair,  are  black ;  the  latter  is  crisped, 
and  the  beard  thin. 

§  116.  The  anatomical  characters  of  the  American  race  are 
less  defined,  and  seem  intermediate  between  the  Caucasian  and 
the  negro.  The  skin  is  of  a  copperish  red  ;  the  hair  is  black, 
straight  and  fine,  and  the  beard  scanty  or  wanting. 

§  117.  The  malay  is  like  the  American,  but  little  distin- 
guished by  characters  drawn  from  anatomy,  he  appears  to  be 
between  the  two  first.  In  this  race,  the  skin  is  brown  or 
tanned,  and  the  hair  thick  and  curly. 

§  118.  Fabulous  varieties  have  also  been  admitted: — this  is 
no  place  to  speak  of  them.  Albinos  originate  from  a  morbid 
change.  In  each  race  we  also  find  sub-varieties  more  or  less 
marked.  In  different  countries,  often  nearly  approximated,  we 
generally  observe  a  national  character,  at  least,  as  regards  the 
physiognomy;  but  in  each  race  also,  in  each  nation,  and  even 
in  much  more  limited  divisions,  we  sometimes  find  individuals 
very  different  from  others;  thus  it  is  by  no  means  very 
rare,  that  we  find  in  the  negro,  all  the  anatomical  and  phy- 
siological characters  of  the  Caucasian  race,  colour  excepted, 
and  vice  versa.  The  varieties,  otherwise,  are  confounded  by 
insensible  gradations.  We  must  then  consider  these  varieties 
in  the  species,  as  accidental  differences  only,  the  causes  of 
15 


104  INTRODUCTION. 

which,  it  is  true,  are  not  easy  to  determine,  but  how  confined 
also,  are  the  observations  made  on  such  a  subject,  and  conse- 
quently how  unequal  to  the  determining  of  the  conditions  of  a 
phenomenon  for  the  production  of  which  nature  has  spared  no 
time. 


OP  THE  ALTERATIONS  OF  THE  ORGANIZATION. 

§  119.  The  human  body  does  not  always  arrive  at  the  term 
of  its  existence  by  a  progressive  alteration  of  the  organization. 
Most  generally  the  development  stops,  deviates  from  the  usual 
course,  or  the  organization  regularly  developed,  becomes  al- 
tered by  the  action  of  external  agents.  The  body  thus  altered 
in  its  conformation,  in  its  texture,  in  its  composition,  is  the  sub- 
ject of  morbid  anatomy.  To  the  physician,  this  kind  of  anato- 
my is  the  necessary  compliment  of  the  anatomy  of  the  healthy 
body;  it  is  to  pathology,  what  ordinary  anatomy  is  to  phy- 
siology; pathology  can  no  more  exist  without  morbid  anato- 
my, than  physiology  without  anatomy;  there  can  no  more  be 
morbid  phenomena  or  symptoms  without  altered  organs,  than 
functions  without  regular  organs,  than  phenomena  without  bo- 
dies, motion  without  matter.  Morbid  anatomy  is  the  founda- 
tion of  pathology. 

§  120.  The  derangements  of  the  organization,  may  affect  the 
conformation  of  the  body,  in  general,  or  of  some  organs:  this 
constitutes  a  first  class,  that  of  vices  of  conformation.  Some 
are  original  or  primitive,  others  are  secondary  or  acquired. 
These  latter  are  numerous  and  very  different  from  each  other. 
As  to  the  first,  attentive  observation  has  caused  the  discovery 
of  one  of  the  most  important  laws  of  the  development  of  the 
organization.  These  vices,  are  in  fact,  and  essentially,  only  a 
permanent  state,  in  one  or  several  organs,  stadia  or  degrees, 
through  which  they  pass  in  the  progressive  development. 
Thus,  for  instance,  the  numerous  vices  which  consist  in  a  fis- 
sure or  separation,  more  or  less  great,  on  the  median  line,  as 
the  hair-lip,  that  of  the  roof  of  the  mouth,  or  of  the  velum  pa- 
lati,  the  opening  of  the  sternum,  of  the  diaphragm,  of  the  wall 
of  the  abdomen,  of  the  anterior  parietes  of  the  bladder,  of  the 


ALTERATIONS  OP  THE  ORGANIZATION.  105 

pubis,  of  the  urethra,  of  the  perineum,  spina  bifida,  cranium 
bifidum,  etc.  are  merely  the  permanent  state  of  a  fissure,  which 
should  only  be  temporary. 

The  junction  of  the  fingers,  the  prolongation  of  the  coccyx, 
the  persistence  of  the  pupillary  membrane,  the  bifid  uterus,  the 
testicle  in  the  abdpmen,  etc,  are  merely,  situations,  divisions, 
reunions,  states  of  continuance  of  organs,  which  ought  only  to  be 
temporary,  and  which  have  remained  permanent.  It  is  the  same 
with  the  anormal  communications  of  the  cavities  of  the  heart, 
of  the  opening  of  the  bladder  at  the  umbilicus,  of  the  existence 
of  a  cloaca  and  congenital  umbilical  hernia. 

Sometimes,  it  happens,  that  when  one  of  these  vices  exists, 
the  rest  of  the  organization  is  developed,  nearly,  as  usual;  but 
in  certain  cases,  one  imperfection  is  the  unavoidable  cause  of 
others,  and  here  is  one  of  the  most  striking  examples;  if  the 
olfactory  nerve  and  ethmoidal  bone  which  contain  it,  are  ar- 
rested in  their  development,  the  orbits  and  the  eyes  will  be- 
come more  or  less  intimately  confounded,  and  will  constitute 
what  is  called  a  cyclops.  *  It  is  the  same  with  respect  to  seve- 
ral others. 

This  part  of  pathological  antomy,  which  has  been  regarded 
as  a  mere  matter  of  curiosity,  is  on  the  contrary,  of  great  in- 
terest to  the  physiologist,  and  the  pathologist. 

§  121.  The  derangements  of  the  organization,  may  also  consist 
in  an  alteration  of  the  texture,  and  composition  of  the  organs. 
The  following  are  the  effects  and  productions  of  irritation, 
of  inflammation,  and  of  other  less  known  derangements  of  the 
secretions,  and  of  nutrition:  adhesion,  generally,  and  the  dif- 
ferences it  presents  in  the  various  divided  organs;  pus  and 
other  liquid  products  of  inflammation;  transformations  of  one 
tissue  into  another  resembling  healthy  tissues;  the  degenera- 
tion or  the  changing  of  an  organ  into  a  substance  that  has  no 
analogy  with  anything  in  the  regular  organization;  the  hard 
or  soft  concretions  which  are  formed  in  the  ducts  and  reser- 
voirs of  follicles  and  glands,  and  which  are  owing  to  an  altera- 
tion in  the  liqui'd  secreted,  and  in  the  secretory  organ,  are  so 

*  See  Beclard.  Memoir es  sur  les  foetus  acfyhales. 


106  INTRODUCTION. 

many  highly  important  genera  of  this  class,  the  study  of  which, 
is  of  no  doubtful  use,  as  may  appear  that  of  the  vices  of  con- 
formation. 

We  must  add  to  these  two  classes,  that  of  intestinal  worms 
sufficiently  numerous,  and  that  of  the  parasitic  animals  which 
may  exist  in  man. 

OF  DEATH  AND  THE   CADAVER.* 

§  122.  Deatht  is  the  final  and  total  cessation  of  the  functions 
of  life,  soon  followed  by  the  dissolution  of  the  body.  It  is  the 
necessary  and  inevitable  result  of  the  successive  changes  of  the 
organism.  It  is  seldom,  however,  the  last  term  of  life  arrived 
to  extreme  old  age;  most  generally  it  is  occasioned  by  acci- 
dental causes. 

Life  consists,  essentially,  in  the  reciprocal  action  of  the  cir- 
culation of  the  blood,  and  of  inner vation,  death  always  results 
from  the  cessation  of  this  action.  Senile  death,  appears  to  re- 
sult from  the  simultaneous  weakening  of  these  two  functions, 
and  the  simultaneous  alteration  of  their  organs,  and  morbid  or 
accidental  death  from  the  primitive  alteration  of  one  of  the 
two  organs,  and  of  its  function.  It  is  always,  in  fact,  by  the 
interruption  of  the  nervous  action  upon  the  organs  of  the  cir- 
culation, or  by  the  cessation  of  the  action  of  the  blood  on  the 
nervous  centre,  that  death  is  determined  by  accident  or  disease. 
But  the  blood  may  cease  to'act  upon  the  nervous  system,  so  as 
to  continue  life;  either  because  the  heart  no  longer  sends  it 
there,  and  that  the  vessels  cease  to  conduct  it  effectually;  or 
because  the  blood  is  no  longer  submitted  to  respiration;  or  be- 
cause it  is  not  purified  by  the  secretions  from  noxious  princi- 
ples, by  the  urinary  depuration  in  particular;  or  because  the 
intestinal  digestion  and  absorption  do  not  furnish  it  with  nu- 
tritious materials;  or,  finally,  because  deleterious  substances 
are  car/ied  into  the  mass  of  this  fluid  from  without. 

§  123.    The  cadavert  is  a  dead,  organized  body;  but  this 

*  We  prefer  this  word,  although  not  English,  to  any  paraphrase.  The 
cadaver,  is  the  body  after  the  extinction  of  life.  TRANS. 

f  See  Chaussier.   Table  des  phenomtnes  cadaveriques. 


OP  DEATH  AND  THE  CADAVER.  107 

term  is  particularly  applied  to  an  animal,  and  chiefly  to  man, 
who  has  ceased  to  live.  The  body,  in  which  the  vital  action 
is  insensible,  soon  looses  its  heat  and  mobility.  For  a  few 
moments  after,  we  may  observe  in  it  some  particular  pheno- 
mena the  last  vestiges  of  that  life  which  has  just  ended,  and 
which  are  called  primitive  cadaveric  symptoms.  But  the  ca- 
daver has  an  ephemeral  duration  only.  Putrefaction  always 
commences  after  a  certain  and  generally,  very  short  time, 
unless  under  peculiar  circumstances;  its  elements  separate, 
and  the  bones  alone  remain  for  a  while,  to  be  destroyed 
in  their  turn.  Although  all  dead  bodies  are  disposed  to 
the  changes  of  which  we  are  speaking,  all  do  not  alter  in 
the  same  space  of  time,  or  in  the  same  manner.  The  age  and 
constitution  of  the  individual,  the  proportion  of  his  humours, 
the  nature  of  his  death,  the  circumstances  which  have  pro- 
ceeded it,  the  season,  climate,  state  of  the  atmosphere,  the 
bodies  which  surround  the  corpse,  &c.,  are  all  so  many  cir- 
cumstances, each  of  which  has  an  influence,  sui  generis,  upon 
the  development  of  cadaverous  phenomena;  besides  this,  each 
organ  undergoes  peculiar  changes.  The  following  are  the  most 
general  alterations  that  ensue: 

§  124.  The  warmth,  as  well  as  the  other  phenomena  of  nutri- 
tion, sometimes  diminishes  immediately  previous  to  death, 
and  ceases  altogether  shortly  after.  The  cooling  takes  place 
gradually  and  commences  at  the  surfaces  and  extremities.  It 
proceeds  so  much  the  faster,  as  the  subject  is  the  more  ex- 
hausted by  old  age  or  disease,  deprived  of  blood,  lean, and  the 
atmosphere  more  cold;  under  these  circumstances  it  may  be 
effected  in  two  or  three  hours,  whereas  it  generally  requires 
fifteen  or  twenty  hours;  it  may  even  require  several  days. 
The  blood  is  blackish,  and  generally  preserves  its  fluidity  and 
motion  while  the  body  is  warm;  the  aorta  and  principal  arte- 
ries are  emptied:  it  accumulates  most  commonly  in  the  vena 
cava,  in  the  auricles  of  the  heart,  the  vessels  of  the  lungs  and 
even  in  the  veins  generally,  a  circumstance  resulting  from  the 
elasticity  of  the  arteries  and  bronchia?  and  from  the  mechan- 
ism of  the  chest.  The  accumulation  of  blood  in  the  veins 
varies  according  to  the  causes  of  death;  where  there  has  been 


108  INTRODUCTION. 

dyspnea  or  suffocation,  it  is  very  considerable,  and  in  this  case, 
there  are  sometimes  congestions,  turgenscenscies,  erections, 
and  even  sanguineous  transudations.  The  blood,  obeying  its 
gravity  and  the  action  of  the  arteries,  accumulates  and  forms 
livid  spots  in  those  parts  that  are  dependent  at  the  moment  of 
death,  and  while  the  body  is  yet  warm,  the  rest  of  it  remain- 
ing pale  and  yellowish.  During  all  this  period  of  cooling, 
the  body  is  in  general  soft  and  flexible,  the  eyes  half  open,  the 
lower  lip  and  jaw  pendent,  the  pupil  dilated:  congestions  that 
have  existed  during  life,  sometimes  disappear;  the  sphincters 
are  relaxed,  and  sometimes,  through  a  remaining  vestige  of 
contractibility,  an  expulsion  of  the  faeces  takes  place,  and 
even  parturition.  The  muscles  may  yet  be  irritated  by  vari- 
ous stimuli,  by  galvanism  particularly. 

§  125.  The  soft  parts  remain  flexible  and  the  blood  fluid,  as 
long  as  the  body  preserves  its  warmth;  no  sooner  has  that 
abandoned  it,  than  the  blood  coagulates,  and  the  soft  parts 
become  stiffened  in  a  greater  or  less  degree.  The  coagulation 
of  the  blood  varies  greatly;  generally  it  is  either  white  or  le- 
mon coloured  concretions,  which  are  moulded  in  the  vessels; 
sometimes  the  blood  assumes  the  consistence  of  jelly,  or  even 
remains  completely  fluid.  The  cadaverous  stiffness  is  a  con- 
stant phenomenon,  and  is  characterized  by  the  firmness  of  the 
soft  parts  and  the  resistence  and  immobility  of  the  articula- 
tions. It  begins  in  the  trunk  and  extends  first  to  the  superior, 
and  then  to  the  inferior  extremities.  This  phenomenon  which 
appears  to  depend,  essentially,  on  the  last  contraction  of  the 
muscles,  and  also  on  the  general  cooling  and  coagulation  of 
the  fluids,  presents  a  great  difference  as  regards  the  moment 
of  its  manifestation,  its  intensity  and  its  duration.  Thus  in 
death  from  old  age,  in  that  induced  by  a  slow  exhaustion  or 
by  excessive  fatigue,  from  gangrenous,  putrid,  or  scorbutic 
diseases,  &c. ,  the  stiffness  ensues  very  promptly,  is  not  very 
intense,  and  scarcely  lasts  for  one  or  two  hours.  On  the  con- 
trary in  strong,  muscular  subjects,  who  expire  suddenly  by 
violence;  after  most  asphyxies  and  acute  diseases,  the  stiffness 
does  not  come  on  for  twenty  or  thirty  hours,  becomes  very 
considerable  and  remains  for  three  or  four  days.  The  rigidity 


OF  DEATH  AND  THE  CADAVER.  109 

of  the  soft  parts,  afterward  spontaneously  ceases,  and  in  the 
same  order  of  its  manifestation;  it  is  replaced  by  a  softness 
that  gradually  augments;  the  parts  are  abandoned  to  their 
gravity,  take  a  consequent  direction  and  sink.  The  coagu- 
lated fluids  become  again  liquified,  and  their  fluidity  even 
seems  to  increase.  Such  are  the  first  phenomena  of  putrid 
decomposition. 

§  126.  In  some  cases  and  most  commonly  after  a  sudden 
and  violent  death,  there  is  a  considerable  and  rapid  disen- 
gagement of  gas,  either  in  the  intestinal  canal,  the  serous  cavi- 
ties, the  cellular  tissue  or  even  in  the  vessels  themselves:  from 
this  result  other  various  remarkable  phenomena.  The  tym- 
panites of  the  abdomen  pushing  up  the  diaphram,  freqently 
occasions  a  discharge  of  mucus  from  the  mouth  or  nares,  and 
sends  the  blood  to  the  neck  and  head:  whence,  the  swelling 
of  the  face,  the  lustre  of  the  eye,  the  contraction  of  the  pupil; 
it  also  causes  a  reflux  of  the  matter  in  the  stomach  to  the 
pharynx,  larynx,  the  nasal  fossa  or  the  mouth;  it  also  occa- 
sions a  determination  of  blood  to  the  genitals,  the  excretion  of 
gas,  of  faeces,  and  sometimes,  even  a  rupture  of  the  abdominal 
parietes.  The  development  of  gas  in  the  cellular  tissue  con- 
stitutes the  cadaverous  emphysema;  its  disengagement  in  the 
heart  and  vessels  occasions  a  motion  in  the  blood  and  even 
its  flow  from  wounds,  phenomena  styled,  cadaverous  cruen- 
tation. 

§  127.  Putrefaction  is  an  intestinal  movement,  the  inverse 
of  the  organic  action,  which  establishes  itself  in  the  body,  de- 
stroys all  the  combinations,  which  were  formed  by  the  vital 
action,  separates  their  molecules,  reduces  them  to  a  simpler 
state  of  composition,  reduces  them  to  gas,  vapours,  putres- 
cence and  earth,  and  thus  restoring  them  to  the  general  mass 
of  inert  bodies.  Besides  the  cessation  of  life,  putrefaction  re- 
quires as  other  requisites,  the  contact  of  air,  and  a  certain  de- 
gree of  heat  and  humidity.  The  extent  and  combination  of 
these  requisites,  occasion  much  variety  in  the  phenomena  of 
decomposition. 

§  128.  It  commences  commonly,  the  instant  the  coagula- 
tion and  rigidity  cease:  from  that  moment  the  liquids  begin 


110  INTRODUCTION. 

to  be  resolved,  and  the  soft  parts,  gradually,  to  soften  and  re- 
lax. The  body,  which  exhales  from  the  beginning  a  vapour, 
whose  loss  diminishes  its  weight,  then  gives  out  a  stale  and 
musly  odour.  The  blood  and  other  humours  transude  from 
their  reservoirs,  and  impregnate  the  surrounding  parietes  and 
parts  with  their  colour  and  odour:  thence  the  colouring  of  the 
veins  and  surrounding  cellular  tissue  which  is  red,  the  spots 
printed  on  the  stomach  and  the  intestines,  by  the  liver,  the 
spleen  and  gall-bladder,  the  sero-sanguineous  infiltrations  in 
the  cellular  tissue  and  serous  membranes,  their  rose,  red  and 
brown  colours,  and  the  tinging  of  the  abdomenal  parietes  with 
a  bluish  or  greenish  tint.  The  humours  of  the  eyes  transude, 
whence  the  destruction  of  the  cornea  and  by  mingling  with 
the  corpuscules  that  flit  about  in  the  eye,  they  form  a  slimy 
coat  or  covering. 

In  this  first  period,  the  muscles  redden  litmus  paper. 

§  129.  Putrefaction,  which,  as  respects  the  regions,  gene- 
rally commences  in  the  abdomen,  on  account,  of  theexcremen- 
titial  matter  there  accumulated;  which,  as  respects  the  organs, 
begins  in  the  softest  and  such  as  are  the  most  impregnated 
with  fluids,  as  the  encephalic  mass,  and  which  also  first  attacks 
engorged  parts,  or  such  as  have  been  altered  by  disease  or  the 
kind  of  death,  soon  becomes  general.  The  epidermis  is  de- 
tached, and  raised  by  masses  of  a  brownish  sanies;  the  muscles 
by  the  imbibition  of  the  fluids  become  glutinous,  greenish, 
pulpy  and  ammoniacal;  a  putrid  and  nauseating  odour  is  dis- 
engaged. 

§  130.  Finally  the  texture  disappears  in  toto;  the  soft  parts, 
confounded  with  the  fluids  are  reduced  into  a  half  fluid  pu- 
trescence, mixed  with  bubbles  of  gas,  exhaling  the  most  infec- 
tious odour,  and  the  most  pernicious  vapour.  Soon,  nought 
remains  but  the  bones,  which  in  their  turn  become  friable  and 
pulverulent,  leaving  nothing  but  a  small  earthy  residuum. 

§  131.  When  the  conditions  of  putrefaction  are  favourable, 
as  after  certain  diseases  and  in  hot  and  humid  times  and  places, 
it  commences  at  the  moment  of  death,  and  runs  through  its 
stages  with  the  greatest  rapidity.  Under  contrary  circum- 
stances it  is  slow,  and  may  be  completed  only  after  the  lapse 


OF  DEATH  AND  OF  THE  CADAVER.  Ill 

of  years.  It  may  be  even  indefinitely  suspended,  or  its  phe- 
nomena much  modified.  Thus  a  body  enclosed  by  ice,  may 
be  preserved  without  undergoing  any  sensible  change,  as  long 
as  the  congelation  lasts:  thus  also,  a  body  dessicated  by  a  dry 
and  hot  atmosphere,  like  that  of  the  deserts  of  Africa,  or  by  an 
absorbent  earth,  as  in  certain  caves,  or  by  the  heat  of  the  oven 
or  stove,  or  by  various  chemical  operations,  may  become  near- 
ly imputrescent.  In  like  manner,  a  body  plunged  into  the  wa- 
ter and  kept  there,  in  humid  earth,  or  in  one  saturated  with 
cadaverous  products,  may  be  transformed  into  adipocire,  be- 
come saponified  by  the  reciprocal  action  of  its  fat,  and  the  am- 
monia, which  results  from  the  decomposition  of  the  flesh. 

§  132.  The  body,  for  some  time  after  death,  still  preserving 
nearly  the  same  organization  and  composition  as  when  alive, 
is  the  subject  on  which  anatomy  is  studied.  As  numerous 
changes,  however,  which  continue  to  augment,  commence 
from  the  moment  of  death,  we  must,  by  the  examination  of 
living  animals,  rectify  the  ideas  we  have  acquired  by  that  of 
bodies  deprived  of  life. 

Every  subject  is  not  equally  fit  and  proper  for  the  study  of 
anatomy.  For  long  and  consecutive  dissections,  we  should  not 
select  those  which  have  yielded  to  putrid  diseases,  or  fatigue, 
those  that  are  still  warm,  or  those  in  which  putrefaction  has 
been  rapid  or  is  much  advanced:  extreme  cleanliness  is  abso- 
lutely necessary  in  all  anatomical  researches.  If  a  wound  is 
received  while  dissecting,  particularly  if  the  subject  be  not  a 
proper  one,  it  should  be  washed  and  cauterized  on  the  spot. 

§  133.  The  anatomist,  considers  in  each  solid  part  of  the  bo- 
dy, 1st,  its  configuration  or  its  form,  external  as  well  as  in- 
ternal, if  it  is  hollow,  and  its  position,  whether  symmetrical  or 
irregular;  2d,  its  situation  in  the  whole  body,  and  relative  to 
other  parts,  as  well  as  its  relations  of  contact  or  connexion, 
more  or  less  intimate  with  them;  3d,  the  direction  of  its  great 
diameter  which  may  be  parallel,  oblique,  or  perpendicular  to 
the  axis  of  the  body ;  its  metrical  extent  either  as  relates  to  the 
body  or  some  of  its  parts  ;  5th,  its  physical  proportions,  either 
as  relative  to  the  attraction  of  its  molecules,  as  its  density,  its 

cohesion,  elasticity,  &c.  or  as  relates  to  the  manner  in  which  it 
16 


112  INTRODUCTION. 

is  affected  by  light,  as  its  colour  and  transparency ;  6th,  its  ana- 
tomical composition  and  its  texture,  or  the  arrangement  of  its 
integral  parts;  7th,  its  properties  and  chemical  composition; 
8th,  the  liquids  or  humours  it  contains ;  9th,  the  properties  it 
enjoyed  during  life  ;  10th,  its  vital  actions,  and  the  connexion 
of  this  action  with  the  others;  llth,  the  varieties  it  presents  in 
the  ages,  sexes,  races,  and  individuals  ;  12th,  its  morbid  states, 
and  13th,  its  cadaverous  phenomena  and  changes.  Although 
several  of  these  considerations  seem  to  belong  to  the  study  of 
natural  philosophy,  chemistry,  physiology,  and  pathology,  ra- 
ther than  anatomy,  there  is  none  of  them  that  will  not  en- 
lighten the  anatomist,  not  one  of  them  that  he  should  neglect. 


GENERAL  ANATOMY. 


CHAPTER  I. 

OP  THE  CELLULAR  AND  ADIPOSE  TISSUES. 

§  134.  These  two  tissues  have  been  generally  confounded 
under  the  name  of  cellular  tissue;  they  are,  however,  very  dif- 
ferent, and  should  be  separately  described. 

SECTION  I. 

OF  THE  CELLULAR  TISSUE. 

§  135.  The  cellular  tissue,  has  been  so  called,  on  account  of 
the  areolae  it  forms,  improperly,  perhaps,  styled  cells.  It  is  a 
soft  spongy  tissue,  extending  through  the  whole  body,  sur- 
rounding all  the  organs,  uniting  them,  and  at  the  same  time 
separating  them  from  each  other;  it  penetrates  into  their  sub- 
stance, and  has  the  same  mode  of  existence  with  all  their  parts ; 
entering  into  the  composition  of  all  organized  bodies,  and  of  all 
organs,  it  is  the  principal  element  of  organization. 

According  to  the  light  in  which  it  has  been  viewed,  the  dif- 
ferent names  of  substance,  body,  system,  organ,  membrane, 
cribrous,  mucous,  glutinous,  intermediate,  areolar,  reticulated, 
laminous,  filamentous  tissue,  &c.  have  been  given  to  it.  The 
name  of  cellular  tissue  is  perhaps  no  better  than  the  others;  it 
is,  however,  more  generally  adopted. 

§  136.  Notwithstanding  the  very  great  extent  and  import- 
ance of  this  tissue,  which  must  have  arrested  the  attention  of 
anatomists,  at  an  early  period,  no  description  of  it  is  to  be 
found  in  ancient  authors.  Hippocrates,  speaks  of  the  gener 
ral  permeability  of  the  tissues,  when  he  says,  that  the  whole 


114  GENERAL  ANATOMY. 

body  perspires  without,  as  well  as  within:  the  first  ideas  of  the 
existence  of  the  cellular  tissue,  have  been  sought  for  in  this 
passage.  What  Erasistratus  called  parenchyma,  corresponds, 
perhaps,  with  this  tissue.  But  we  find  no  exact  ideas,  as  to  its 
disposition,  until  the  time  of  Charles  Etienne,  Vesalius,  and 
Adrian  Spigel :  even  these  anatomists,  and  a  great  many  of 
those  who  succeeded  them,  have  only  indicated  the  cellular 
tissue,  in  the  different  places  where  it  is  met  with,  as  around 
the  vessels,  muscles,  fat,  &c.  Kaaw  Boerhaave,  Bergen  and 
Winslow,  were  the  first  who  published  some  general  ideas,  on 
the  continuity  of  this  tissue,  in  the  different  regions;  but  it  is 
since  the  time  of  Haller,  only,  that  it  has  been  presented  to  us 
in  a  correct  point  of  view.  The  cellular  tissue  has  occasioned 
many  treatises.  Schobinger,  Thierry,  W.  Hunter,  Bordeu, 
Fouquet,  Wolff,  Detten,  Luca3,  de  Felici,  paid  particular  at- 
tention to  it.  Their  works  have  added  but  little  to  the  de- 
scription given  by  Haller ;  but  several  of  them  are  remarka- 
ble* for  ideas,  more  or  less  correct,  of  the  nature  and  func- 
tions of  this  tissue.  All  anatomists,  and  those  in  particular, 
who  occupied  themselves  with  general  anatomy,  have  spoken 
of  it  in  their  books:  Mascagni,  alone,  scarcely  names  it.  There 
are  no  good  plates  of  the  cellular  tissue,  in  fact,  having  no  de- 
termined form  or  colour,  it  is  impossible  to  represent  it; 
Wolff  has  made  the  experiment,  but  has  failed. 

§  137.  In  order  to  facilitate  the  study  of  the  cellular  tissue, 
we  examine  it  successively,  in  two  portions,  of  which  one  is 
considered  as  independent  of  the  organs,  and  as  merely  filling 

*Dav.  Ch.  Schobinger.  De  telsc  cellulosae,  in  fobrica  corporis  humani,-  dig- 
nitate.  Gott.  1748. — Fr.  Thierry.  Ergo  in  celluloso  textu  frequentius  morbi  et 
morborum  mutationes.  Paris.  1749,  1757,  1788.— W.  Hunter.  Remarks  on 
the  cellular  membrane,  etc,  in  Med.  Obs.  and  Inq.  vsl.  II.  London  1757. — Th. 
de  Bordeu  Rccherches  sur  le  tissu  muqueux  ou  Porgane  cellulaire,  etc.  Paris 
1767. — Fouquet  and  Abadie.  De  corpore  criboso  Hippocratis.  Monsp.  1774 — 
C.  F.  Wolf.  De  tela  quam  dicunt  cdlulosam  observationes,  in  nova  act  a  Jicad. 
Sc.  Imp.  Pctrop.  vol.  vi,  vii,  viii,  1790,  1791 — M.  Uetten.  Beytrag  etc.  viz. 
supplement  to  the  study  of  the  functions  of  the  cellular  tissue.  Munster, 
1800. — S.  H.  Lucre,  .ftnnotationes  circa  telam  cellulosam,  in  obs.  circa  nemos, 
etc.  Franc,  ad  Moen.  1810. — G.  M.  de  Felici.  Cennl  di  una  nuova  idea,  sulla 
natura  del  tcssuto  cellulare.  Pavia,  1817. 


OP  THE  CELLULAR  TISSUE.  115 

the  spaces  between  them,  while  the  other  relates  only  to  the 
organs  it  envelops  and  inlo  whose  texture  it  enters.  These 
portions  or  divisions  are  distinct,  in  imagination  only,  for  the 
cellular  tissue  is  every  where  continuous  with  itself. 

§  137.  The  first  portion  is  the  external,  general  or  common 
cellular  tissue — textus  cellular  is  inter  medius,seu  laxus — that 
which  does  not  penetrate  into  the  organs.  This  common  cel- 
lular tissue  has  the  general  extent  and  form  of  the  body;  if  we 
could  suppose  all  other  organs  to  be  removed,  and  that  this 
tissue  could  support  itself,  it  would  form  a  whole,  preserving 
the  form  of  the  body  and  presenting  a  number  of  cells  or  ca- 
vities for  the  different  organs.  The  thickness  of  the  layer  it 
forms  round  each  of  the  latter,  is  not  every  where  the  same.  In 
the  vertebral  canal  the  cellular  tissue  is  but  in  a  very  small 
quantity;  in  the  interior  of  the  cranium,  it  forms  an  almost 
invisible  layer,  so  great  is  its  tenacity.  More  of  it  is  found  on 
the  exterior  of  these  same  parts:  it  is  particularly  abundant 
about  the  spine,  in  front,  especially.  The  different  parts  of 
the  face,  the  orbits,  the  cheeks,  contain  a  large  quantity. 
There  is  also  a  great  deal  in  the  neck,  along  the  vessels  and 
between  the  muscles,  in  the  thorax  between  the  layers  of  the 
mediastinum,  and  on  the  exterior  of  this  cavity  round  the 
mammae.  A  great  quantity  of  cellular  tissue  is  contained  in 
the  abdomen,  both  in  its  interior,  and  in  the  thickness  of  its 
parietes.  This  tissue  abounds  in  the  groin,  axilla,  among  the 
hamstrings,  in  the  palm  of  the  hand  and  the  sole  of  the  foot; 
between  the  muscles  it  forms  layers,  more  or  less  thick.  Gene- 
rally speaking,  it  is  the  more  importantorgans  that  are  most  sur- 
rounded by  the  cellular  tissue;  this  tissue  is  also  most  plenty 
in  those  places  that  are  the  seats  of  great  motions.  Besides  as 
it  envelops  all  the  organs  and  every  where  forms  the  parti- 
tions that  divide  them,  other  circumstances  being  equal,  there 
should  be  most  of  it  wherever  these  organs  are  most  numer- 
ous: accordingly,  this  is  what  we  find,  in  the  neck. 

§  139.  The  continuity  of  the  cellular  tissue  is  particularly 
apparent  in  the  great  spaces  between  the  organs.  In  the  neck, 
the  continuity  of  this  tissue  with  that  of  the  head  above,  and 


116  GENERAL  ANATOMY. 

with  that  of  the  interior  of  the  thorax  below,  is  evident:  the 
openings  of  this  cavity  which  communicate  with  the  superior 
members,  present  an  equally  well  marked  continuity  of  the 
cellular  tissue  of  the  chest  with  that  of  the  superior  members. 
In  a  similar  way  in  the  abdomen,  the  ischiatic  notch,  the  in- 
guinal ring,  the  crural  arch,  &c.  present,  an  evident  continui- 
ty of  the  cellular  tissue  within  the  abdomen  and  without,  and 
hence  with  the  inferior  members.  The  intervertebral  foramina 
along  the  vertebral  canal,  establish  a  communication  between 
the  interior  and  exterior  of  the  canal;  the  foramina  at  the  base  of 
the  cranium  establish  in  like  manner  a  communication  between 
its  cavity  and  the  outside  of  the  head.  The  continuity  of  the 
cellular  membrane  does  not  only  exist  in  the  places  of  which 
we  have  spoken;  various  phenomena,  of  which  more  here- 
after, indicate  it  generally  in  all  the  spaces  that  subsist  be- 
tween the  organs;  it  is  only  more  strongly  marked,  wherever 
these  spaces  are  most  sensibly  defined.  It  will  easily  be  per- 
ceived that  the  rounded  forms  of  the  organs,  must  render  these 
spaces  very  numerous. 

§  140.  The  second  division  of  the  cellular  tissue,  furnishes 
to  each  organ  in  particular,  an  envelope  which  is  peculiar  to 
it, and  which  besides  penetrates  into  its  thickness;  this  peculiar 
disposition,  has  given  rise  to  two  sub-divisions.  The  cellu- 
lar tissue  which  forms  the  envelopes  of  organs — textus  cellu- 
laris  strictus — has  been  considered  by  Bordeu  as  a  kind  of 
atmosphere,  which  limits  their  morbid  action  and  phenomena, 
and  prevents  these  latter  from  being  extended  from  one  to 
another.  This  idea,  adopted  by  Bichat,  appears  to  me  to  have 
but  a  slight  foundation;  the  difference  of  their  organization  is 
the  sole  cause  of  the  insulation  which  the  organs  present  in 
their  actions,  as  well  as  in  their  diseases.  Be  this  as  it  may, 
the  cellular  layer  which  surrounds  the  organs  varies  in  thick- 
ness— they  all  show  this  in  a  degree  more  or  less  marked,  those 
only  excepted,  whose  envelopes  are  of  a  different  nature,  that 
is,  of  the  ligamentous  or  serous  tissues.  The  envelope  which 
this  layer  constitutes,  is  continuous  with  the  common  cellular 
tissue  on  the  one  hand,  and  with  that  which  occupies  the  inte- 
rior of  the  organ, on  the  other.  Its  cellular  envelope  is  variously 


OF  THE  CELLULAR  TISSUE.  117 

disposed,  according  to  the  form  of  the  latter.  The  skin,  the 
mucous  and  serous  membranes,  the  blood  vessels,  lympha- 
tics and  excretory  canals  which  have  only  one  surface  free, 
are  connected  with  the  cellular  tissue  on  one  side  only,  the 
solid  organs  on  the  contrary,  such  as  the  muscles,  are  entirely 
surrounded  by  it.  Under  the  skin  the  cellular  tissue  forms  a 
layer  generally  extended,  if  we  except  the  places  where  the 
muscles  and  aponeuroses  are  inserted.  This  sub-cutaneous 
tissue  is  more  or  less  dense,  according  to  the  region  it  occu- 
pies; it  is  the  most  so  throughout  the  whole  extent  of  the 
median  line,  at  the  neck  excepted,  where  this  line  is  but 
slightly  defined.  Bordeu  has  exaggerated  this  disposition  in  say- 
ing that  it  divides  the  body  into  two  halves:  it  is  very  evident, 
that  at  a  certain  depth  no  traces  of  it  are  to  be  seen.  In  those 
places  where  there  is  great  motion,  the  cellular  tissue  is 
more  lax,  as  in  the  eye-lids,  prepuce,  scrotum,  lips  and  vulva. 
On  the  contrary,  where  the  skin  does  not  slide,  as  in  the 
palm  of  the  hand,  the  sole  of  the  foot,  front  of  the  sternum, 
back,  &c.  it  is  tighter.  The  mucous  membranes  have  their 
adhering  surfaces  covered  by  a  very  dense  cellular  tissue, 
usually  styled  the  nervous  membrane.  That  which  covers 
the  adhering  surfaces  of  the  serous  membranes  is  generally 
flaky.  That  which  is  found  round  the  canals,  forms  particu- 
lar sheaths  for  them,  particularly  important  to  the  arteries,  but 
it  is  also  found  about  the  veins,  lymphatic  trunks  and  excre- 
tory ducts.  This  tissue  forms  a  layer  round  the  muscles,  called 
their  common  membrane. 

§  141.  That  portion  of  the  cellular  tissue  which  penetrates 
into  the  organs,  which  accompanies  and  envelopes  all  their 
parts — textus  cellularis  stipatus—i&  differently  disposed  in 
the  different  organs.  In  the  muscles  it  forms  an  envelope  for 
each  fasciculus,  and  smaller  ones  for  the  secondary  fasciculi  and 
for  the  fibres  of  which  these  latter  are  composed:  thus  the  cel- 
lular tissue  of  a  muscle  exhibits  a  series  of  canals,  sheathed  suc- 
cessively within  each  other,  and  connected  in  the  same  way  that 
the  envelopes  belonging  to  the  different  organs  continue  with 
the  general  envelope  of  the  body.  The  lobes  of  the  glands,  their 
lobules,  and  the  grains  which  compose  these  latter,  are  sur- 


118  GENERAL  ANATOMY. 

rounded  in  the  same  way  by  successively  smaller,  cellular 
envelopes,  and  which,  apart  from  the  rest  of  the  gland,  would 
form  a  sort  of  cellular  sponge.  The  organs  composed  of  seve- 
ral membranous  layers,  as  the  stomach,  the  intestine  and 
bladder  have  cellular  tissue  between  their  different  layers. 
Certain  very  compound  organs,  as  the  lungs,  have  more  or 
less  cellular  tissue  round  each  of  the  parts  which  enter  into 
their  structure:  the  quantity  of  cellular  tissue  is  generally 
proportioned  to  the  number  of  different  parts  that  the  organ 
contains.  For  in  proportion  as  the  cellular  tissue  is  divided 
and  subdivided  to  embrace  the  finer  parts  of  the  organs,  it 
becomes  itself  finer,  and  its  envelope  thinner;  thus  it  is  that 
the  small  arteries  are  surrounded  by  a  finer  tissue  than  the 
larger  ones.  The  envelopes  formed  by  the  cellular  tissue  are 
in  general  thicker,  in  proportion  as  the  parts  execute  more  mo- 
tions, hence  the  predominance  of  this  tissue  in  the  muscles  over 
the  glands.  Certain  organs,  such  as  ligaments,  tendons,  bones 
and  cartilages  have  no  free  and  distinct  cellular  tissue  in  their 
thickness.  In  order  that  it  be  apparent,  it  is  necessary  gene- 
rally that  the  organs  present  appreciable  intervals  between 
their  component  parts:  thus  the  ligaments  which  have  appa- 
rent fibres,  show  the  cellular  tissue  that  separate  these  fibres — 
in  the  others  none  is  to  be  found. 

§  142.  Not  only  does  the  cellular  tissue  enter  into  the  com- 
position of  all  the  organs,  it  also  forms  the  basis  of  them  all — 
textus  organicus,  seu  parenchymalis — and  composes  per  se, 
several  of  them:  this  it  is,  or  the  fibre  or  substance  that  forms 
it,  if  you  will,  that  constitutes  (varying  only  in  degrees  of 
consistence)  the  serous  membranes,  the  dermis,  the  vessels, 
the  ligamentous  tissue,  in  a  word,  almost  all  the  parts,  with 
the  exception  of  the  nerves  and  muscles,  even  these,  differ 
from  it  only  in  the  addition  of  the  globules.  The  horny  and 
epidermic  parts,  alone  have  nothing  in  common  with  the  cel- 
lular tissue.  Haller  and  some  other  anatomists  have  placed 
the  spongy  or  cavernous  tissues  and  aerial  vesicles  of  the 
lungs  in  the  cellular  tissue;  but  these  parts  have  a  peculiar 
disposition,  which  will  not  allow  them  to  be  confounded  with 
the  cellular  tissue.  The  cavities  of  the  hyaloid  membrane, 


OF  THE  CELLULAR  TISSUE.  1  t  5 

also,  included  by  Haller  in  the  tissue  of  which  we  are  speak- 
ing, should  be  distinguished  from  it. 

§  143.  Anatomists  have  not  yet  agreed  on  the  internal  con- 
formation of  the  cellular  tissue.  Some  of  them,  with  Haller, 
considering  it  as  having  distinct  cells,  of  a  determined  form 
and  size,  made  by  the  multiplied  intercrossings  of  laminae  and 
filaments.  Others  again,  as  Bordeu,  Wolff,  and  Meckel,  say 
that  this  tissue  is  merely  a  viscous,  tenacious,  coutinuous  sub- 
stance, unfurnished  with  laminae  and  cells,  and  that  these  lat- 
ter, when  they  do  exist;  are  the  result  of  the  operations  made 
to  demonstrate  them.  The  following  is  what  we  learn  upon 
this  subject  by  inspection. 

When  we  examine  the  section  of  a  muscle  by  the  glass,  we 
perceive  that  the  fibres  are  not  in  contact,  but  are  separated 
by  a  transparent  substance;  if  we  draw  aside  these  fibres,  this 
substance  forms  filaments,  which  are  extended  as  we  draw, 
and  finally  break.  Those  who  look  upon  the  cellular  tissue  as 
a  sort  of  gluten,  take  this  opportunity  to  remark,  that  it  would 
be  precisely  thus,  if  these  fibres  were  separated  by  glue. 
Around  the  entire  muscle,  we  find  an  evident  lamina,  which, 
in  the  same  way,  by  distension,  takes  the  form  of  filaments; 
by  blowing  air  under  this  lamina,  it  is  transformed  into  irregu- 
lar cells,  separated  by  species  of  partitions.  It  would  appear 
then,  that  round  the  smaller  parts,  the  cellular  tissue,  is  really 
a  sort  of  jelly,  while  around  the  larger,  its  laminae  are  appa- 
rent If,  instead  of  air,  we  inject  water,  and  freeze  it  there, 
irregular  crystals  filling  the  cells  are  obtained:  a  similar  result 
follows  the  injection  of  a  coagulable  matter.  But  these  cells 
are  never  regularly  disposed,  nor  are  their  forms  geometrical, 
as  has  been  said  ;  their  figure  may  even  vary,  when  produced 
at  repeated  trials  in  the  same  spot. 

Whether  the  laminae,  fibres,  and  cells,  are  pre-existent  in 
the  cellular  tissue,  or  whether  they  depend  only  on  its  separa- 
tion, is  a  question,  on  which,  as  we  have  seen,  there  is  much 
doubt.  Possessed  of  a  sufficiently  distinct  organization,  where- 
ever  its  thickness  is  considerable,  this  tissue  seems  inorganic 
in  those  places  where  it  is  thinner,  and  even  different  between 
the  smaller  fibres  of  the  muscles.  In  admitting  the  existence 


120  GENERAL  ANATOMY. 

of  the  cells,  should  we  regard  them  as  closed  on  all  sides,  and 
communicating  only  after  the  rupture  of  their  walls,  or  as 
pierced  or  porous  cells,  opening  into  those  adjoining,  or  finally, 
as  areola,  spaces  open  on  all  sides,  like  those  irregular  ones, 
which  subsist  between  the  fibres  and  laminae  of  the  cellular 
tissue?  The  latter  appears  the  most  probable.  But  these  areolae 
in  their  ordinary  state,  are  of  an  extreme  smallness,  micro- 
scopic with  contiguous  parietes,  and  the  enlargement  they  ex- 
perience by  infiltration,  inflation,  etc,  tearing  and  altering  them 
greatly,  can  give  no  exact  idea  respecting  them. 

§  144.  The  cellular  tissue,  in  other  respects,  is  precisely  as 
though  it  were  spongy,  liquids  and  gases  penetrating  it  with 
the  greatest  facility.  In  fact,  1st,  the  serum,  in  the  dropsy 
of  this  tissue,  always  flows  into  its  most  depending  parts,  or 
into  those  which  offer  the  least  resistance;  the  situation  of  the 
patient  has  much  influence,  as  to  the  place  it  occupies;  exter- 
nal pressure  displaces  it  equally;  one  single  incision  often  suf- 
fices for  its  issue;  2d,  the  water  thrown  in  by  artificial  injec- 
tions, flows  through  the  cellular  tissue  in  the  same  manner 
from  cell  to  cell;  3d,  air  infiltrated  in  emphysema,  and  that 
which  is  artificially  introduced,  present  the  same  phenomena; 
4th,  in  echymosis,  the  blood  is  infiltrated  in  a  similar  way, 
spreads  extensively  through  the  cellular  tissue,  and  is  dissemi- 
nated more  and  more.  All  this  demonstrates  a  general  com- 
munication between  the  areolae:  those  who  do  not  admit  these 
to  exist,  explain  these  facts  by  the  slight  consistence  of  the 
cellular  tissue.  Whether  the  areolar  fibres  or  lamina,  of  the 
cellular  tissue,  be  inherent  in  this  tissue,  or  are  only  the  effects 
of  the  various  agents  of  distension,  it  is  always  certain,  that  in 
this  respect,  it  presents  remarkable  differences.  In  certain 
places  it  is  always  fibrous  or  filamentous;  in  others,  it  is  chiefly 
laminated,  or  lameliated,  as  in  the  eye-lids,  scrotum,  prepuce, 
the  labia  of  the  vulva,  and  between  the  very  moveable  mus- 
cles; the  more  soft  and  lameliated,  the  larger  are  the  areolae  it 
forms;  and  these  large  areolae.  seem  to  be  the  first  rudiments 
of  the  serous  cavities. 

§  145.  When  in  thin  lamina  the  cellular  tissue  is  colourless; 
it  appears  whitish  when  its  thickness  is  increased,  and  particu- 


OF  THE  CELLULAR  TISSUE.  121 

larly  when  distended;  it  is  semi-diaphanous.  Its  powers  of 
cohesion  varies ;  in  some  places,  as  between  the  muscular  fi- 
brilli,  it  is  simply  that  of  a  slightly  viscid  liquid ;  in  others 
again,  its  resistance  is  almost  equal  to  that  of  the  fibrous  tissue. 
This  tissue  is  very  extensible,  and  very  retractile,  as  may  be 
seen  by  inflating  it,  and  making  an  incision,  it  then  contracts 
forcibly,  driving  out  the  distending  air.  Its  chemical  proper- 
ties have  been  carefully  studied  by  Bichat.  Deprived  of  wa- 
ter by  dessication,  it  loses  a  part  of  its  physical  qualities,  and 
acquires  new  ones;  in  this  state,  it  is  hygrometrical,  and  re- 
sumes its  original  aspect  when  placed  in  water,  a  peculiarity 
it  possesses  in  common  with  almost  all  the  organic  tissues. 
Exposed  to  heat  it  dries  rapidly,  becomes  crisp,  and  ends  in 
burning  like  all  the  other  tissues,  leaving,  however,  but  little 
ashes.  It  strongly  resists  decoction,  and  is  dissolved  only  by 
long  continued  ebullition.  It  putrefies  very  slowly:  to  accom- 
plish the  entire  decomposition  of  this  tissue,  by  maceration,  re- 
quires several  months,  even  without  renewing  the  water;  it  is 
converted  at  last  into  a  viscid  substance  resembling  mucilage, 
and  furnishes  divers  products  which  rise  to  the  surface  of  the 
liquid.  Fourcroy  considered  it  composed  of  gelatin;  John 
detected  in  it  besides,  a  small  quantity  of  fibrin,  and  the  phos- 
phate and  carbonate  of  lime. 

§  146.  The  intimate  nature  of  the  cellular  texture,  has  given 
rise  to  a  great  number  of  hypotheses.  Ruysch  supposes  it  to 
be  entirely  vascular;  Mascagni,  who  scarcely  mentions  it,  says 
it  is  composed  of  white  vessels;  Fontana  of  tortuous  cylinders; 
others  regard  it  as  an  expansion  of  the  nerves.  The  only  base 
we  should  admit  in  it,  is  the  cellular  fibre  or  substance,  68,  85. 
It  is  traversed  by  a  great  number  of  vessels,  and  serous  vessels 
particularly;  but  it  should  not  be  considered  as  wholly  consist- 
ing of  them,  for  it  is  it  that  definitely  forms  the  parietes  of  the 
extreme  vessels.  The  cellular  tissue  has  canals  or  cavities  pe- 
culiar to  it.  They  are  the  little  spaces  or  areolae  with  which  it 
is  hollowed,  or  that  the  liquids  excavate  as  fast  as  they  are  de- 
posited in  it,  and  which  by  their  communication  make  it  a 
spongy  and  permeable  body.  Almost  all  those  who  have  paid 
particular  attention  to  injections,  Haller,  Albinus,  Prochaska, 


GENERAL  ANATOMY. 

&c.  have  placed  it  among  the  solid  or  non-injectable  parts,  q 
v.  d.  that  it  is  without  the  circulating  track  of  the  vessels.  The 
blood,  nevertheless,  may  pass  into  its  canals  or  peculiar  cavi- 
ties, but  then  there  is  inflammation.  The  nerves,  in  like  man- 
ner, do  not  appear  to  stop  or  terminate  in  the  cellular  tissue. 
This  tissue  forms  a  true  and  separate  substance,  traversed  by 
nerves  and  blood-vessels  in  every  direction,  and  in  which  a 
liquid  is  left  by  the  latter  only. 

§  147.  It  is,  in  fact,  continually  bathed  and  humected  by  a 
very  tenuous  liquid,  which  it  imbibes,  and  whose  quantity  is 
so  small  as  to  be  scarcely  sensible;  the  word  vapour  is  conse- 
quently used  to  designate  this  fluid.  If  we  make  an  incision, 
in  the  cellular  tissue  of  a  living  animal,  it  is  this  liquid  that 
moistens  the  fingers;  introduced  into  the  wound  in  cold 
weather,  a  vapour  arises  from  the  divided  tissues,  that  is  con- 
densed and  rendered  visible,  by  the  external  air;  it  arises  both 
from  the  cellular  tissue  and  the  white  vessels.  In  anasarca,  the 
liquid  of  the  cellular  tissue,  accumulated,  and  perhaps  altered, 
greatly  resembles  the  serum  of  dropsical  patients;  it  is  coagula- 
ble  like  the  latter,  and  appears  even  to  contain  a  certain  quan- 
tity of  albumen,  water,  and  some  salts. 

§  148.  The  cellular  tissue  is  the  first  part  formed  in  the  em- 
bryo; it  is  also  found  in  the  very  lowest  order  of  animals.  This 
tissue,  at  first  liquid,  and  very  abundant,  diminishes  in  propor- 
tion as  the  organs  become  developed,  and  acquires  consistence 
at  the  same  time.  Even  at  birth,  it  is  still  diffluent  in  the  in- 
terstices of  the  muscles,  and  very  soft  under  the  skin.  Its  den- 
sity continues  to  increase  in  old  men,  and  it  is  almost  fibrous 
at  a  very  advanced  age  in  those  parts  which  in  the  infant  are 
very  soft.  The  cellular  tissue  is  looser  and  more  abundant  in 
women  than  in  men.  JBlurnenbach,  gives  as  a  character  of  the 
organization  of  man,  compared  to  that  of  other  animals,  the 
presenting  of  a  softer  and  tenderer  tissue,  which  gives  him  a 
greater  facility  of  motion. 

§  149.  The  power  of  formation  of  the  cellular  tissue  is  high> 
Jy  developed:  it  is  the  first  part  formed;  it  increases  acciden- 
tally, is  completely  formed  at  once  and  is  reproduced  when 
it  has  been  destroyed,  with  the  greatest  promptitude,  as  is 


OP  THE  CELLULAR  TISSUE.  123 

seen  in  wounds,  adhesions,  &c.  It  possesses  a  power  of  con- 
traction depending  in  part,  upon  its  elasticity  and  partly  upon 
its  irritability.  This  latter  quality  is  here  called,  fibrillary, 
staminal,  tonic  contractility:  it  is  manifested  by  the  motions 
of  the  liquid  this  tissue  generally  or  accidentally  contains, 
and  by  the  general  or  local  tightening  it  experiences  in  vari- 
ous cases;  it  is  not  very  evident  that  the  nervous  force  influ- 
ences or  determines  its  contractions.  It  has  no  sensibility 
except  in  a  state  of  inflammation. 

§  150.  The  uses  and  functions  of  the  cellular  tissue  are  very 
important;  it  is  it  that  determines  the  form  of  all  the  parts.  It 
is  the  only  lien  that  unites  them  with  each  other:  upon  its 
cohesion  depends  that  of  all  the  other  tissue.  By  its  elasticity, 
it  facilitates  the  movements  and  replaces  the  organs  in  the  state 
they  were  in  previous  to  being  displaced,  when  these  move- 
ments have  ceased :  thus  £<so  do  these  latter  perform  their 
functions  the  more  easily  in  proportion  as  the  cellular  tissue 
is  perfect. 

It  is  the  seat  of  a  perspiratory  secretion  which  on  account 
of  its  extent  is  very  abundant.  Does  the  liquid  there  given 
out  by  the  extreme  vessels  experience  a  sort  of  circulation  or 
movement  of  translation?  Of  this  we  are  totally  ignorant. 
It  is  only  in  cases  of  morbid  accumulation,  that  we  see  the 
infiltrated  liquid  change  its  place  in  obedience  to  weight  and 
pressure,  &c.  It  has  been  supposed,  but  without  any  solid 
reason,  that  this  liquid  is  in  a  state  of  continual  agitation,  of 
which  the  diaphragm,  by  its  alternate  motions  upwards  and 
downwards,  is  the  principal  cause;  that  there  are  currents  in 
various  directions  and  that,  for  example,  it  is  the  secret  way 
by  which  liquids  pass  from  the  stomach  to  the  bladder,  a  sup- 
position disproved  by  all  exact  observations;  that  it  is  the  chan- 
nel of  metastasis,  &c.  However  it  may  be,  the  liquid  is  after- 
wards taken  back  again  by  the  vessels,  so  that  this  tissue  is 
intermediate  between  perspiration  and  resorption.  The  tonic 
contraction  of  the  cellular  tissue  is  the  agent  that  propels  the 
serum  of  this  tissue  into  the  vessels. 

The  cellular  tissue  is  in  fact  the  essential  organ  of  absorp- 
tion ;  it  forms  the  mucous  body  of  the  skin,  the  spongy  sub- 


124  GENERAL  ANATOMY. 

stance  of  the  villosities  of  the  mucous  membranes,  parts  which 
absorb,  and  whence,  absorbed  substances  pass  into  the  vessels. 
Previous  to  being  brought  into  the  vessels,  the  matters  ob- 
sorbed  by  the  cellular  tissue,  which  by  way  of  opposition  to 
the  rest  we  may  call  external  or  superficial,  no  doubt  undergo 
elaboration  or  changes.  As  foreign  matters,  before  entering 
the  vessels,  have  to  pass  through  the  cellular  tissue,  the  organ 
of  absorption,  so  also  those  which  are  thrown  out  from  the 
vessels,  traverse  the  cellular  tissue,  the  organ  of  secretion, 
previous  to  being  deposited  on  the  surfaces  on  which  they 
are  poured. 

The  cellular  tissue  which  envelops  each  organ  in  particular, 
has  been  considered  as  forming  for  it  an  isolating  atmosphere, 
which  circumscribes  its  actions,  whether  hygid  or  morbid: 
observation  frequently  contradicts  this  assertion,  and  when 
the  fact  is  so,  it  is  in  the  peculiar  texture  of  the  organ  and  the 
variety  of  agents,  that  we  must  seek  an  explanation,  and  not 
in  this  pretended  atmosphere. 

The  cellular  tissue  which  penetrates  into  the  thickness  of 
the  organs,  reunites  all  their  parts. 

As  to  the  organic  cellular  tissue  or  parenchyma,  it  forms 
the  base  or  essential  element  of  each  organ,  and  presents  these 
remarkable  differences.  In  the  most  rational  hypothesis  re- 
specting the  seat  of  nutrition^  it  is  admitted  that  the  nutritive 
matter  is  deposited  out  of  the  vessels  in  the  cellular  substance, 
which  is  the  base  of  the  organs,  to  be  assimilated  to  them,  and 
that  it  is  thus,  the  essential  organ  of  nutrition.  However  it 
may  be  as  to  the  hypothetical  uses,  attributed  to  the  cellular 
tissue,  it  has  incontestably  very  important  ones  in  the  organ- 
ism. 

§151.  The  phenomena  of  the  cellular  tissue  either  in  health 
or  sickness,  are  connected  with  those  of  the  other  parts.  Thus 
organic  lesions  of  the  heart,  and  the  derangements  of  the  pul- 
monary respiration  and  perspiration,  often  occasion  there  an 
accumulation  of  serum.  The  same  thing  takes  place  in  the 
alterations  of  various  secretions,  that  of  cutaneous  transpira- 
tion particularly.  Its  inflammations,  generally  cause  fever. 
The  suppurative  inflammation  which  is  occasioned  in  it  by 


OF  THE  CELLULAR  TISSUE.  125 

seton,  &c.  frequently  reduces  the  inflammations  of  the  other 
organs. 

§  152.  The  cellular  tissue  is  subject  to  various  morbid 
changes.  When  broken  into  and  exposed,  it  inflames,  becomes 
covered  with  fleshy  buds,  suppurates,  and  at  last  covers  it 
\vith  a  cicatrix  or  new  skin  which  will  be  described  hereafter. 
(Chap,  iii.) 

When  it  is  cut  and  its  divided  surfaces  are  again  brought 
into  contact,  they,  at  first,  agglutinate  by  means  of  a  liquid 
poured  out  from  the  divided  surfaces  when  the  bleeding  and 
pain  have  ceased.  A  little  later,  and  this  organizable  substance 
becomes  a  highly  vascular  tissue:  then  it  is  no  longer  possi- 
ble to  separate  the  lips  of  the  wound  without  renewing  the 
pain,  and  reproducing  the  flow  of  blood.  This  new  tissue  re- 
mains  for  a  long  time,  more  compact,  firm  and  vascular  than 
the  cellular  tissue  it  unites  and  with  which  it  is  at  last  con- 
founded. 

It  is  by  a  similar  process  that  every  union  of  divided  parts 
.takes  place,  with  modifications  relative  to  each  tissue,  which 
will  be  examined  in  their  proper  place. 

It  is,  also,  in  this  way  that  adhesions  are  formed  between 
contiguous  surfaces  of  the  serous  arid  tegumentary  membranes, 
adhesions  that  will  be  described  when  we  come  to  treat  of 
membranes.  (Chap,  ii,  iii.) 

The  cellular  tissue  is  susceptible  of  an  extroardinary  growth : 
when  exposed,  it  sometimes  shoots  out  in  a  kind  of  vegetation 
or  vascular  exuberances.  The  reproduction  of  this  tissue  is  in 
general  so  much  the  easier,  as  the  quantity  that  remains  in 
the  spot  from  which  it  was  taken  is  great:  it  seems  that  this 
reproduction  depends,  in  a  great  measure,  upon  the  extension 
of  the  pre-existing  cellular  tissue. 

The  inflammation  of  the  cellular  tissue,  or  phlegmon,  is 
characterized  by  various  changes  in  this  tissue.  The  first  of 
these  changes,  is  a  highly  marked  increase  of  vascularity. 
The  inflamed  cellular  tissue  becomes,  besides,  sensible  and 
painful;  it  entirely  loses  its  permeability;  liquids  can  no  longer 
pass  through  it;  its  consistence  augments  and  its  tenacity  di- 
.m.inishes;  pressure  tears  and  breaks,  instead  of  elongating  it, 


126  GENERAL  ANATOMY. 

as  before.  This  sort  of  fragility  which  the  cellular  tissue  ac- 
quires, explains  certain  phenomena;  it  explains  why  the  liga- 
ture of  a  vessel  frequently  produces  a  section  of  the  surround- 
ing tissue,  why  at  the  termination  of  peritonitis,  it  is  so  easy 
to  separate  the  intestine  from  the  coat  formed  by  the  perito- 
neum. Inflammation  of  the  cellular  tissue  may  terminate 
insensibly,  and  then  this  tissue  gradually  reassumes  all  its  pro- 
perties: this  is  seen  in  that  kind  of  termination  called,  by  re- 
solution. In  other  cases  the  cellular  tissue  secretes  a  peculiar 
liquid  called  pus,  and  which  will  be  described  hereafter — this 
constitutes  the  termination  by  suppuration.  This  liquid  is 
generally  collected  in  one  point  which  extends  itself  progres- 
sively to  the  circumference,  as  long  as  the  secretion  continues. 
This  is  one  of  the  perspiratory  kind  of  secretions;  pus  is  pro- 
duced directly  from  the  blood  and  even  presents  in  its  com- 
position some  analogy  with  this  fluid.  It  only  requires  the 
disease  to  progress  slowly,  for  the  walls  of  the  abscess  to  be- 
come lined  with  a  membrane.  This  membrane  is  doubled 
externally  by  a  layer,  more  or  less  thick,  of  compact  cellular 
tissue.  This  layer  is  not  so  well  marked  when  the  disease  has 
lasted  a  certain  time,  and  the  membrane  is  then  almost  com- 
pletely isolated,  the  cellular  tissue  having  reacquired  its  pro- 
perties around  it.  Abscesses  are  the  seats  of  a  continual 
secretion  and  absorption;  the  entire  absorption  of  the  pus 
they  contain,  and  the  effects  which  the  presence  of  this  fluid 
sometimes  produces  in  the  economy  are  proofs  of  it.  The  pus 
formed  in  the  interior  of  abscesses  most  commonly  arrives  at 
last  at  the  surface.  The  abscess  is  emptied,  its  walls  are  con- 
tracted, remain  indurated  for  some  time,  and  end  by  reassuming 
all  the  characters  of  cellular  tissue.  When  the  secretion  and 
flow  of  pus  continue,  the  canal  by  which  the  abscess  commu- 
nicates without,  and  which  is  called  sinus  or  fistula,  becomes 
invested  with  a  distinct  membrane,  that  presents  the  charac- 
ters of  the  mucous  membranes,  and  whose  history  belongs  to 
that  of  the  latter.  After  certain  gangrenous  inflammations 
the  cellular  tissue  becomes  so  tightened  by  the  loss  of  sub- 
stance it  has  undergone,  that  the  skin,  the  muscles,  and  the 
aponeuroses  become  confounded:  but  in  this  case,  if  the  pa- 


OF  THE  CELLULAR  TISSUE.  12V 

tient  is  young  and  robust,  the  cellular  tissue  can  be  repro- 
duced with  all  its  properties.  The  inflammation  of  the  cellu- 
lar tissue  sometimes  continues  for  an  indefinite  period,  so 
that  it  remains  hard  and  impermeable :  this  constitutes  in- 
duration. This  state  is  found  in  the  callosities  of  ulcers  and 
fistulas,  which  are  evident  results  of  a  chronic  inflammation  of 
the  cellular  tissue.  The  Barbadoes  disease,a  species  of  elephan- 
tiasis, presents  similar  characters  of  induration. 

New-born  children  are  subject  to  an  induration  of  the  cel- 
lular tissue,  in  which  the  inflammatory  character  is  not  found: 
this  induration  is  observed  under  the  skin,  and  sometimes  in 
the  spaces  between  the  muscles.  It  is  according  to  the  ob- 
servations of  M.  Breschet,  merely  a  secondary  phenomenon 
of  the  imperfect  closure  of  the  foramen  ovale,  or  of  a  defec- 
tive or  imperfect  respiration. 

Air  may  pass  into  the  cellular  tissue;  this  constitutes  em- 
physema. When  the  patient  does  not  die  from  this  accident, 
the  rarified  air  escapes  through  the  incisions  made  for  that  pur- 
pose, or  through  the  wounds  that  may  have  previously  existed, 
or  it  may  combine  with  the  fluids  found  in  the  cellular  tissue, 
and  disappear  by  absorption.  Leucophlegmatis  or  anasarca, 
consists  of  an  accumulation  of  serum  in  the  cellular  tissue.  In 
ecchymosis,thecellular  tissue  contains  blood  dispersed  through 
its  areolas.  All  the  organic  fluids  may  pass  accidentally  into 
this  tissue,  in  which,  when  they  are  of  an  excrementitial  na- 
ture, they  occasion  inflammations  more  or  less  violent. 

Solid  foreign  bodies,  introduced  into  the  cellular  tissue,  do 
not,  commonly,  remain  long  in  the  same  place,  but  like  pus, 
are  generally  carried  to  the  surface,  and  if  they  are  heavy,  par- 
tially obeying  the  laws  of  gravition.  It  is  very  evident,  that  it 
is  not  by  traversing  pretended  cells,  that  these  bodies  travel 
thus  across  and  through  the  cellular  tissue.  The  latter  pre- 
sents around  them,  three  distinct  phenomena:  it  secretes  pus 
around  their  surfaces,  it  re-unites  and  re-assumes  its  softness 
and  permeability  behind,  and  ulcerates  before  them.  Here,  then, 
we  find  three  of  the  kinds  of  inflammation  admitted  by  John 
Hunter,  viz:  Jthe  adhesive,  suppurative,  and  ulcerative :  the 
ensemble  of  these  phenomena  has  received  the  name  of  eli- 
18 


128  GENERAL  ANATOMY. 

minative  inflammation.  It  sometimes  happens  that  foreign 
bodies  remain  in  the  cellular  tissue,  either  on  account  of  the 
lightness  of  their  specific  gravity,  or  of  the  density  of  the  sur- 
rounding tissue:  a  membrane,  in  this  case,  is  formed  around 
them. 

The  cellular  tissue  contains,  in  some  cases,  foreign  animated 
bodies  or  worms :  the  cysticercus  cellulosa,  so  called  on  ac- 
count of  its  seat  in  the  cellular  tissue,  ihejllaria  medinensis, 
or  little  dragon,  whose  existence  can  not  be  questioned,  have 
been  found  in  it,  and  in  animals  the  larvae  of  the  oestrus. 

The  cellular  tissue  may  experience  various  changes.  The 
serous,  fibrous,  bony,  and  cartilaginous  transformation,  which 
are  developed  in  the  cellular  tissue,  will  be  described  with  the 
natural  tissues  to  which  they  belong. 

The  cysts,  whose  seat  is  in  the  cellular  tissue,  will  be  like- 
wise spoken  of,  when  treating  of  the  serous  and  tegumentary 
membranes,  to  which  they  are  very  analogous. 

When  an  organ  happens,  accidentally,  to  disappear,  we  say 
it  is  transformed  into  cellular  tissue;  this  is,  perhaps,  not  ex- 
actly correct;  the  cellular  tissue  in  this  case  merely  taking  the 
place  of  the  wasted  organ,  which  previously  kept  it  at  a  distance. 

Various  degenerations  may  be  regarded  as  especially  apper- 
taining to  the  cellular  tissue:  it  is  this  tissue  which  appears  to 
be  their  base,  for  they  are  every  where  similar.  As  they  are 
common,  however,  to  all  the  organs,  I  shall  speak  of  them 
when  I  have  done  with  the  history  of  all  the  other  tissues. 
Wherever,  in  the  interstices  of  the  organs,  the  cellular  tissue 
is  free,  it  is  affected  by  these  degenerations,  as  well  as  in  the 
places  where  it  constitutes  a  part  of  the  organs  themselves. 


SECTION  II. 


•OF  THE  ADIPOSE  TISSUE. 


§  153.  The  adipose  tissue,  so  called  on  account  of  the  fat 
(adeps)  it  contains,  results  from  Ihe  re-union  of  very  small, 
microscopic  vesicles,  clustered  and  grouped  in  greater  or  less 


OF  THE  COMMON  ADIPOSE  TISSUE.  129 

number,  united  by  laminous  cellular  tissue,  and  fulfilling  the 
office  of  a  reservoir  for  the  fat.  It  is  divided  into  two  kinds: 
one  is  the  common  adipose  tissue,  or  fatty  tissue,  properly  so 
called;  the  other  is  the  adipose  or  medullary  tissue  of  the  bones. 


ARTICLE  FIRST. 
OF  THE  COMMON  ADIPOSE  TISSUE. 

§  154.  This  has  been  called  the  fatty  cellular  tissue,  fatty 
membrane,  web,  tunick,  adipose,  vesicles,  &c.:  it  has  also  been 
styled  the  fatty  pannicle,  because  it  forms  a  layer  immediately 
under  the  skin. 

§  155.  This  tissue,  for  a  long  time,  was  confounded,  with 
the  cellular  tissue,  which  was  sometimes  said  to  contain  se- 
rum, and  at  others  fat,  and  in  the  latter  case,  to  constitute  the 
fatty  tissue.  Malpighi,  was  one  of  the  first  who  raised  a  doubt 
on  this  subject,  and  who  saw  the  fat  form  a  kind  of  grains  at- 
tached to  the  blood-vessels.  Swammerdam  has  also  seen  that 
the  fat  is  a  liquid  oil  inclosed  in  little  membranes.  Morgagni 
acknowledges,  also,  that  the  fat  contains  grains  which  he  corn-- 
pares to  those  of  glands.  Bergen  was  one  of  the  earliest 
writers  who  distinguished  two  kinds  of  cellular  tissue,  one  of 
which,  called  by  him  luminous,  corresponds  to  the  fatty  tissue. 
W.  Hunter  has  given  the  distinctive  characters  of  this  tissue, 
characters  afterwards  acknowledged,  and  more  or  less  exactly 
determined  by  Jarisen,  Wolff,  M.  Chaussier,  Prochaska,  Gor- 
don, Mascagni,  myself  &c.  Haller  denies  the  existence  of 
this  tissue,  admitting  only  the  areolae  of  the  cellular  tissue  as 
parts  containing  fat;  his  opinion  has  been  adopted  by  Bichat, 
M.  Meckel,  &c.;  we  shall  see,  however,  further  on,  that  this 
opinion  is  but  slightly  founded.  The  fatty  tissue  has  been 
carefully  described  in  several  works,*  and  figured  in  some  of 
them.t 

*  M.  Malpighi,  De  omento,  pinguedine,  etc.  in  ejusd.  op.  onin  et  posthum. — 
Bergen,  op.  cit. — W.  Hunter,  op.  tit. — Wolff,  op.  dt. — W.  X.  Jansen.  Pin- 
guedinis  animalis  consideratio  physiologica  et  pathologica.  Lug-d.  bat.  1784. 

f  Mascagni.  Prodrome  della  grande  anatomia. 


130  GENERAL  ANATOMY. 

§  156.  The  adipose  tissue  presents  appearances  varying  ac- 
cording to  the  places  where  it  is  examined.  Under  the  skin 
it  forms  a  layer  more  or  less  thick  and  everywhere  extended. 
In  the  orbits,  in  the  thickness  of  the  cheeks,  in  the  interior  of 
the  pelvis,  front  of  the  pubis,  about  the  kidneys,  &c.,  it  re- 
sembles rounded  masses.  On  the  loose  edge  of  the  epiploon, 
in  the  epiploical  appendages  of  the  intestine,  and  on  the  level 
of  the  openings  which  are  found  on  the  exterior  of  the  perito- 
neum, these  masses  are  pyriform  and  pediculated.  In  the 
epiploon,  the  fat  is  disposed  in  fillets  or  ribands  that  follow 
the  track  of  the  vessels. 

§  157.  Although  the  fat,  is  not  so  universally  distributed 
as  the  cellular  tissue,  it  is  nevertheless,  found  in  many  places. 

The  vertebral  canal  contains  a  small  portion  of  it  outside 
the  dura-mater.  It  exists  in  considerable  quantities  about  the 
head,  particularly  in  the  face,  in  the  parotid  notches,  in  the 
cheeks,  &c.  In  the  neck  this  tissue  is  more  abundant  behind 
than  before.  In  the  external  and  internal  parts  of  the  thorax  it 
exists  in  remarkable  quantities  in  the  vicinity  of  the  heart,  as 
well  as  between  the  pectoral  muscles  and  about  the  mammae. 
The  fat  of  the  abdomen  is  principally  situated  outside  the  kid- 
neys, in  the  pelvis,  in  the  thickness  of  the  mesentery,  of  the 
epiploon  and  of  the  appendica  epiploicoe.  In  the  limbs,  fat  is 
more  abundant  about  the  articulations  in  the  direction  of  the 
flexion,  as  well  as  in  those  places  that  are  exposed  to  constant 
pressure,  as  the  nates  and  the  sole  of  the  foot. 

The  fatty  tissue  varies  according  to  the  organ  in  which  it  is 
placed.  That  which  is  under  the  skin  always  remains,  cases 
of  extreme  emaciation  excepted,  and  is  continued  into  the 
areolae  of  the  skin.  There  is  none  found  under  the  mucous 
membranes.  The  synovial  and  serous  membranes,  on  the  con- 
trary, are  lined  by  this  tissue,  particulary  in  the  thickness  of 
their  folds.  The  adipose  tissue  which  surrounds  the  muscles, 
penetrates  likewise  into  the  thickness  of  those  that  are  divided 
into  distinct  fasciculi,  as  the  great  glutoeus,  &c.  In  the  lobu- 
late  glands  it  is  seen  in  the  spaces  between  the  lobes.  The 
sheaths  of  vessels,  generally  contains  but  little.  The  large 


OP  THE  COMMON  ADIPOSE  TISSUE.  131 

nerves  as  the  ischiatic  nerve  have  small  masses  of  it  between 
their  fasciculi.     The  fat  in  the  bones  is  considered  separately. 

§  158.  In  particular  parts  no  fat  is  to  be  found,  as  under  the 
skin  of  the  cranium,  of  the  nose,  of  the  ear,  of  the  chin,  where 
the  median  line  is  entirely  deprived  of  it;  there  is  also  but 
very  little  between  the  skin  and  cuticle.  Scarcely  any  is  found 
opposite  the  insertion  of  the  deltoid,  occasioning  that  depres- 
sion which  exists  in  even  the  fattest  subjects.  This  fluid  is 
not  to  be  found,  about  the  long  and  thin  tendons,  nor  in  the 
spaces  of  those  muscles  which  produce  the  great  movements, 
as  between  the  triceps  and  anterior  rectus  femoris,  the  biceps 
and  the  brachialis  externus,  the  gastrocnemii  and  the  soleus. 
The  substance  of  the  viscera  has  seldom  any  fat,  nor  is  there 
any  in  the  parietes  of  the  stomach,  or  of  the  uterus,  in  the  liver 
or  the  spleen.  The  eye-lids,  the  penis,  the  small  labia  pu- 
dendi,  are  also  deprived  of  it.  The  quantity  of  fat  existing 
in  the  human  body,  greatly  varies ;  but  in  some  parts  of  it 
none  can  be  found,  not  even  in  the  most  excessive  state  of 
obesity,  while  on  the  contrary  there  are  others,  in  which  the 
most  complete  marasmus  never  cause  it  to  disappear  entire- 
ly. In  the  adult  man  of  ordinary  plumpness,  the  fat  forms 
about  the  twentieth  part  of  the  weight  of  the  body. 

§  159.  The  fatty  tissue  is  generally  of  a  yellowish  white 
colour  and  of  a  soft  consistence,  but  varying  according  to  the 
region  to  which  it  belongs,  the  age,  &c. 

§  160.  Whatever  be  the  external  form  of  the  adipose  tissue, 
the  masses  it  presents  are  divided  into  smaller  ones,  from  the 
size  of  a  pea  to  that  of  a  filbert,  smaller  about  the  head,  larger 
round  the  kidneys.  These  masses  are  buried  in  the  cellular 
tissue;  their  form  varies;  generally  rounded,  it  is  elongated, 
ovoid  on  the  median  line  of  the  abdomen,  one  of  the  eMremi- 
ties  holding  by  the  skin,  the  other  by  the  aponeuroses.  By 
dissection  we  can  reduce  them  into  adipose  lobules  or  grains, 
which  examined  microscopically,  appear  themselves  to  be 
composed  of  an  infinitude  of  little  vesicles,  from  the  sixth  to 
the  eight  hundredth  part  of  an  inch  in  diameter.  We  may  then 
consider  the  fatty  tissue  as  composed  of  conglomerate  vesi- 
cles, united  in  grains,  which  in  their  turn,  are  collected  to 


132  GENERAL  ANATOMY. 

form  masses.  The  result  of  this  disposition  is  that  the  struc- 
ture of  this  tissue  is  not  areolar,  but  rather  resembles  that  of 
the  fruits  of  the  family  of  the  hesperides,  such  as  oranges  and 
lemons  which  present  in  the  same  way,  and  very  plainly, 
^membranous  vesicles  attached  to  partitions  that  divide  them. 
'The  fatty  vesicles,  as  well  as  the  grains  and  the  masses  which 
they  form,  are  furnished  with  small  foot-stalks,  formed  by  the 
vessels  situated  in  the  intervals,  and  may  be  compared,  in  this 
respect,  to  grapes  supported  by  their  pedicles.  These  vesi- 
cles, however,  are  so  excessively  thin  that  it  is  impossible  to 
distinguish  their  parietes;  but  there  are  many  certain  proofs 
of  their  existence.  In  fact,  if  the  fat  were  loose  or  free,  it 
would  not  form  regular  and  distinct  masses.  It  is  an  error  in 
Haller  and  others  to  pretend  that  this  form  is  proper  to  fat  or 
inherent,  for  it  presents  no  globules,  and  by  itself  has  no  de- 
termined figure.  If  we  place  under  the  microscope,  some  of 
these  vesicles  plunged  into  warm  water,  no  oil  can  be  seen  on 
their  surface;  but  on  breaking  them,  a  few  drops  of  it  escape 
and  float  on  the  surface  of  the  liquid.  Add  to  these  considera- 
tions, that  the  fat  in  the  living  body  being  fluid,  as  is  proved 
by  its  flowing  on  the  division  of  the  tissues,  it  ought  to  pass 
through  like  serum,  if  not  in  health,  at  least  in  disease;  but 
this  never  takes  place,  and  all  that  has  been  said  about  the  in- 
filtration of  fat  to  explain  the  formation  of  the  pendent  mam- 
mae of  certain  nations,  the  salient  buttocks  of  others,  the  dorsal 
humps  of  some  animals  and  the  immense  tails  of  others,  &c., 
presents  only  a  collection  of  contradictory  facts  and  absurd 
reasonings.  Roose  and  Blumenbach  have  argued  against  the 
existence  of  these  vesicles,  from  the  development  of  fat  in 
parts  were  these  little  apparatuses  do  not  exist ;  thence  they 
conclude,  that  these  latter  are  not  necessary  to  the  production 
of  this  fluid:  fat  is,  in  fact,  produced  in  the  cellular  tissue,  but 
it  then  forms  vesicles,  instead  of  being  simply  contained  in 
the  open  areolse. 

§  161.  The  cellular  tissue  between  the  adipose  vesicles  is  very 
delicate,  as  it  commonly  is  between  the  more  tenuous  parts  of 
our  organs:  these  vesicles  seem  scarcely  to  adhere  to  each  other, 
as  they  may  be  separated  without  their  opposing  any  resistance. 


OF  THE  COMMON  ADIPOSE  TISSUE.  133 

The  cellular  tissue  becomes  more  distinct  between  the  adipose 
grains  and  very  apparent  between  the  masses,  the  latter,  in 
some  places,  even  being  separated  by  strong  fibrous  laminae, 
as  may  be  seen  in  the  sole  of  the  foot,  and  whose  use  is  to  give  a 
high  degree  of  elasticity  to  the  fat.  In  other  places,  the  adipose 
masses  are  united  and  supported  by  firm  cellular  laminae, 
as  in  the  cranium,  back,  &c.  in  others  by  a  lax  tissue  as  in 
the  groin,  &c.  In  order,  however,  to  have  a  distinct  view  of 
the  cellular  tissue  that  is  situated  between  the  fatty  lobes,  we 
must  examine  it  in  subjects  affected  with  anasarca  or  emphy- 
sema: by  this  examination  we  shall  also  be  convinced,  that 
the  fat  is  not  free  in  the  areolse  of  the  cellular  tissue;  for  how- 
ever extensive,  however  deep  be  these  infiltrations,  they  may 
separate,  even  dissect,  as  it  were,  the  adipose  grains,  but  the 
fat  is  never  mixed  with  the  infiltrated  fluid. 

The  blood  vessels  of  the  fatty  tissue  are  injected  with  ease. 
They  are  also  very  visible  when  we  examine  those  parts, 
where  the  blood  that  remains  fluid  has  been  naturally  carried 
after  death.  These  vessels  are  most  apparent  in  old  persons, 
the  fatty  lobules  being  more  distinct.  Their  divisions  and 
sub-divisions  end  in  microscopic  vesicles.  Malpighi  once 
thought  that  these  vessels  were  surmounted  with  a  secretory 
apparatus,  and  a  duct  which  emptied  into  the  reservoir  of  the 
fat;  he  afterwards  discovered  and  acknowledged  that  this  dis- 
position did  not  exist.  The  absorbent  vessels  of  the  vesicles 
are  less  known  than  the  veins  and  arteries.  Mascagni,  it  is 
true,  says  they  are  composed  of  an  internal  layer  of  lympha- 
tic vessels,  and  of  an  external  one  of  blood  vessels;  but  he 
produces  no  fact  in  support  of  this  opinion.  It  is  not  known 
whether  or  not  these  vesicles  have  nerves. 

When  there  is  no  fat,  there  are  no  vesicles.  When  this 
fluid  ceases  to  exist  in  a  part,  they  disappear.  Hunter  says, 
however,  that  they  may  be  distinguished  even  when  empty; 
but  I  do  not  think  this  is  so.  Where  they  disappear,  they 
become  confounded  with  the  cellular  element. 

§  162.  Human  fat,  extracted  from  the  fatty  tissue  which 
contains  it,  and  purified,  by  washing,  fusion  and  filtration, 
has  the  general  properties  of  fixed  oils.  It  is  inodorous,  and 


134  GENERAL   ANATOMY. 

of  a  sweet  and  disagreeable  taste;  its  yellowish  colour  is  owing 
to  a  colouring  principle  that  is  soluble  in  water  and  carried  off 
in  washing.  It  is  not  so  heavy  as  water,  its  fusibility  varies 
according  to  its  composition  :  it  is,  in  general,  fluid  at  the  tem- 
perature of  the  body  and  under  it,  sometimes  even  greatly  so, 
as  at  15°R.  for  instance;  it  is  insoluble  in  water,  and-but little  so 
in  cold  alcohol:  it  is  not  acid ;  that  which  Crell  admitted  it  to 
contain,  is  the  result  of  distillation,  an  operation,  in  which  fat 
gives  out  carbonic,  acetic,  and  sebaic  acids,  with  several  other 
products  of  the  reaction  of  its  elements.  It  is  converted  into 
a  sweet  principle,  and  the  margaritic  and  oleic  acids,  by  the 
action  of  strong  alkaline  bases.  Exposed  to  the  air  and  light 
it  becomes  rancid,  producing  a  volatile  acid  of  a  strong  smell. 
The  elementary  composition  of  several  of  the  fats,  has  been 
determined  by  M.  M.  Berrarde,  and  Th.  de  Saussure;  it  is  a 
combination  of  carbone,  hydrogen  and  oxygen,  varying  in 
proportion,  according  to  the  kind  of  animal:  that  of  human  fat 
has  not  been  determined. 

Previous  to  the  labours  of  M.  Chevreul,*  fat  was  considered 
as  a  simple  principle.  He  has  demonstrated  that  it  is  essen- 
tially formed  of  two  organic  materials j  stearine,  fusible  at 
about  50° R.  and  elaine,  fluid  at  zero;  it  is  from  the  proportion 
of  these,  that  results  the  degrees  of  fusibility  of  each  kind  of 
fat.  These  two  direct  materials  are  separated  by  treating  the 
fat  with  boiling  alcohol;  by  cooling,  the  greater  part  of  the 
stearine  is  precipitated  along  with  a  little  elaine,  the  latter  re- 
mains in  solution,  in  the  alcohol,  with  a  small  part  of  stearine. 
We  can  also  separate  them  by  congelation,  which  first  fixes 
the  stearine  with  a  little  elaine.  They  may  also  be  isolated  by 
the  absorption  of  unsized  paper,  which  takes  up  the  elaine  and 
leaves  the  stearine  on  the  surface. 

§  163.  The  fat  of  the  adipose  tissue,  is  not  the  only  fatty 
matter  found  in  animal  organization,  and  in  that  of  man  in 
particular.  A  crystallizable  fatty  substance  is  found  in  the 
blood.  Malpighi,  Haller,  and  others,  thought  that  free  fat  cir- 
culated with  the  blood;  this  is  a  mistake,  at  least,  I  have  never 

*  Annuks  de,  Chimie.  torn.  xciv. — Ann.  de.  Chim,  et  de  Phys.  torn.  ii.  et  vii. 


OF  THE  COMMON  ADIPOSE  TISSUE.  135 

seen  it;  butM.  Chevreul  has  recently  discovered  in  the  blood, 
a  fatty  matter,  held  in  solution  by  the  other  materials  of  that 
fluid.  Butter  is  another  fatty,  coloured  and  odorous  substance, 
held  in  solution  in  the  milk.  There  is  also  in  the  nervous 
substance,  a  fatty,  crystallizable  matter,  analogous  to  that  of 
the  blood.  Finally,  in  cases  of  disease  and  cadaveric  changes, 
other  fatty  matters  are  found  in  the  human  body. 

§  164.  The  adipose  tissue,  in  animals,  presents  some  differ- 
ences; it  exists  in  the  greater  numbers;  it  is  found  in  the  ar- 
ticulata,  the  mollusca,  and  the  vertebrata.  In  the  latter,  the 
fat  presents  various  degrees  of  consistence,  colour,  &c.;  it  is 
very  fluid  in  fishes  and  the  cetacea;  the  head  of  the  physeter 
macrocephalus,  contains  a  liquid  oil,  in  which  is  found  a  con- 
crete fatty  matter,  called  spermaceti  or  cetine.  In  the  hog  it 
is  soft,  forming  lard,  firm  in  the  ruminantia,  where  it  is  called 
tallow,  &c.  The  volume  of  the  adipose  vesicles  is  not  the 
same  in  all  animals:  according  to  Wolff,  they  increase  succes- 
sively, in  the  hen,  the  goose,  man,  the  ox  and  the  hog.  Fat 
accumulates  also,  in  different  regions,  in  different  animals,  as 
on  the  back  of  the  camel,  the  tails  of  some  sheep,  &c.  The 
Bushman  tribe  is  remarkable  for  the  fatty  protuberance  of 
the  rump  in  the  women :  an  example  of  which  has  been  recently 
seen  in  the  Hottentot  Venus,  exhibited  in  Europe. 

§  165.  The  different  degrees  of  plumpness  establish  great 
differences  in  the  quantity  of  fat.  In  a  complete  state  of  obesi- 
ty, it  forms  from  the  half  to  four-fifths  of  the  total  weight  of 
the  body.  In  extreme  leanness,  on  the  contrary  it  exists  only 
in  some  places.  Women  have,  commonly,  more  of  it  than 
men.  It  varies  remarkably,  according  to  age.  The  foetus  has 
none  at  all,  until  the  period  of  gestation  is  half  over.  From 
this  epoch  to  the  birth,  fat  successively  accumulates  in  the  dif- 
ferent parts.  It  is  found  at  first  under  the  skin  only,  and  is 
there  produced  in  isolated  grains,  which  render  its  study  at 
this  age  peculiarly  easy.  At  birth,  a  large  quantity  is  already 
found  under  the  integuments,  and  in  the  thickness  of  the 
cheeks ;  the  epiploon  also,  has  some  isolated  grains  of  it.  The 
quantity  of  fat,augments  with  the  increasing  growth, and  ends  by 

occupying  the  interstices  of  the  muscles,  but  a  long  time  elapses 
19 


136  GENERAL  ANATOMY. 

before  it  is  produced  round  the  viscera.  The  state  of  maturity* 
or  the  period  in  which  the  growth  is  terminated,  is  that  of 
obesity  also:  the  latter  is  sometimes  observable  in  children, 
but  very  rarely.  In  old  age,  the  quantity  of  fat  is  diminished, 
chiefly  under  the  skin  :  this  fluid  then  exists,  especially  in  the 
interior,  as  about  the  heart,  in  the  medullary  cavities  of  the 
bones,  &c. 

§  166.  The  properties  and  functions  of  the  fatty  tissue,  relate 
only  to  the  secretion  of  the  fat.  This  secretion  is  not  made  in 
particular  glands,  nor  in  ducts:  Heister  and  Fanton  were  the 
first  to  doubt  the  existence  of  these  glands,  of  which,  since  the 
error  of  Malpighi  on  this  subject,  many  authors  have  spoken.* 
The  secretion  of  fat  is  a  perspiratory  secretion,  and  Rigel  was 
wrong  in  endeavouring  to  revive  the  theory  of  fatty  ducts, 
which  he  did,  at  the  same  time  he  brought  forward  his  hypo- 
thesis upon  the  use  of  the  renal  capsules:  according  to  this 
author,  the  fat  which  surrounds  the  kidneys  and  its  pelvis,  is 
formed  in  these  capsules,  whence  it  is  carried  by  particular 
ducts,  which  ducts,  however,  he  had  not  been  able  to  inject. 
Does  fat  directly  result  from  the  organic  action  of  the  vessels 
which  deposit  it  in  the  adipose  vesicles?  or,  is  it  already  formed 
in  the  circulating  blood?  or  has  it  a  yet  more  remote  origin? 
M.  Ev.  Hornet  fixes  its  origin  in  the  intestine;  he  thinks,  that 
like  the  chyle,  it  is  a  product  of  digestion,  and  that  it  is  ab- 
sorbed by  the  great  intestine.  This  opinion  is  based,  among 
other  facts,  upon  the  existence  of  the  fat,  or  the  yolk  of  egg, 
in  the  intestine  of  oviparous  vertebrata,  in  the  foetal  or  larval 
state,  and  upon  some  morbid  facts  that  are  not  very  conclusive. 

§  167.  The  fat  is  continually  taken  up  by  the  absorbent  ves- 
sels; the  action  of  these  Vessels  is  demonstrated  by  its  dimin- 
ishing in  quantity  in  several  circumstances.  This  action  is 
equal  to  the  secretion,  when  the  quantity  of  fat  remains  the 
same.  The  exhalation  and  absorption  of  the  fat,  is  occasionally 
very  rapid,  as  proved  by  many  facts.  Children  that  have  be- 
come emaciated,  in  consequence  of  sickness,  resume  all  their 

*  De  usu  glandulctrum  superrenalium  in  anim.  nee  non  de  origine  adipis 
disq.  anat.  philos.  Hasniae,  1790, 
f  Phibsophical  Transactions,  ann.  1813. 


OF  THE  COMMON  ADIPOSE  TISSUE.    '  137 

plumpness  in  a  few  days.  Animals  that  are  famished,  such  as 
hogs,  very  soon  become  fat.  Certain  birds  fatten,  it  is  said,  in 
moist  weather,  in  less  than  twenty-four  hours;  emaciation,  in 
many  cases  is  equally  rapid.  The  circumstances  most  favoura- 
ble to  the  secretion  of  fat,  are  castration,  and  the  absolute  rest 
of  the  animal  and  intellectual  organs.  These  causes  are  fre- 
quently united  when  we  wish  to  fatten  animals :  they  produce 
a  similar  effect  upon  man.  Habitual  bleedings,  sweet  and 
amylaceous  aliments,  are  also  regarded  as  favouring  the  pro- 
duction of  fat.  Besides  these,  there  are  unknown  circum- 
stances, which  appear  to  act  in  the  same  way,  for  we  remark 
extraordinary  cases  of  obesity,  for  which  it  is  difficult  to  ac- 
count. The  causes  which  accelerate  the  absorption  of  the  fat, 
are  in  general,  the  opposite  of  those  above  mentioned,  in  addi- 
tion to  which  are,  abundant  secretions,  organic  diseases,  and 
particularly  those  of  the  organs  of  the  nutritive  functions. 

§  168.  Many  hypothetical  uses  have  been  attributed  to  the 
fat.  Those  which  it  really  possesses,  are  local  and  general. 
In  fact,  the  uses  of  fat  are  in  part  purely  mechanical,  or  of  po- 
sition, such  as  to  lessen  pressure,  in  the  sole  of  the  foot,  in 
standing,  in  the  buttocks  while  sitting,  and  jointly  with  the 
cellular  tissue  to  fill  up  the  hollows,  and  thereby  give  a  round- 
ness to  the  parts;  thus  we  see  those  of  women  and  children  to  be 
the  most  so,  they  having  most  fat.  It  has  been  said,  that  the  fat 
served  as  a  defence  frpm  cold,  because  this  fluid  is  a  bad  con- 
ductor of  heat,  and  that  the  animals  which  inhabit  cold  coun- 
tries, have  a  thick  layer  of  it  under  their  teguments.  Admitting 
this  to  be  so,  it  is  not  by  the  surface  of  the  skin,  at  any  rate, 
that  the  fat  could  preserve  warmth.  It  has  been  asserted,  but 
without  reason,  that  it  lessened  the  nervous  action,  and  the 
action  of  the  muscles,  i.  e.  the  muscular  energy  and  sensi- 
bility: in  this  case,  cause  has  been  mistaken  for  effect.  The 
fat  has  been  thought  to  supple  the  fibres.  Fourcroy,  remem- 
bering that  this  fluid  contains  an  excess  of  hydrogen,  thought 
it  destined  to  render  the  nutritive  substance  more  nitrated,  by 
depriving  it  of  a  part  of  its  hydrogen.  Several  authors,  and 
•even  Bichat  himself  is  inclined  to  the  opinion,  have  thought 
that  the  fat  might  serve  to  oil  the  skin  by  a  sort  of  porous 


138  GENERAL  ANATOMY. 

transudation:  the  sebaceous  follicles  are  too  well  known  at 
present,  to  permit  us  to  adopt  this  idea.  The  general  uses  of 
the  fat  relate  to  nutrition.  Previous  to  being  assimilated,  the 
nutritive  matter  passes  successively  through  various  states; 
fat  is  one  of  the  forms  it  assumes.  Moreover,  this  fluid  may 
be  considered  as  an  aliment  in  reserve:  of  this  various  exam- 
ples are  seen  in  animals.  Insects  for  instance  are  nourished 
by  their  fat  while  in  their  chrysalis  state,  and  present  the  same 
phenomenon  a  little  time  before  their  death.  This  is  still 
more  strongly  marked  in  the  hybernating  animals  which  sleep 
during  the  winter,  and  are  nourished  by  their  fat  only,  until 
they  wake,  at  xvhich  period  they  are  excessively  lean.  The 
foetus  of  the  oviparous  animals  are  nourished  by  the  fat  which 
forms  a  great  proportion  of  the  yolk  of  the  egg. 

§  169.  The  adipose  tissue  and  the  fat,  besides  the  differ- 
ences of  which  we  have  spoken,  present  some  morbid  changes. 

When  the  fatty  tissue  is  divided,  small  drops  of  oil  escape 
and  if  the  lips  of  the  wound  are  maintained  in  contact,  reunion 
soon  takes  place;  but  the  fat  reappears  in  the  place  of  reunion, 
only,  when  the  new  cellular  tissue  has  ceased  to  be  compact. 
The  denuded  fatty  tissue  becomes  inflamed,  the  fat  is  absorbed ; 
it  then  covers  itself  with  a  layer  of  organizable  matter,  which 
becomes  the  base  of  the  cicatrix  or  new  skin  that  is  formed 
over  the  fat. 

This  tissue  and  the  fat  it  contains  sometimes  accumulate  in 
great  quanities,  as  is  seen  in  obesity  or  polysarca.  Individuals 
have  been  seen  in  this  state  weighing  five  or  six  and  some- 
time eight  hundred  pounds.  When  the  obesity  is  local,  or 
limited  to  a  part  of  the  body  it  is  called  Jipoma.*  This  dis- 
ease may  have  its  seat  any  where;  it  is  most  commonly  seen 
however  under  the  teguments,  and  outside  the  serous  mem- 
branes. Tumours  of  this  kind  seated  under  the  skin,  have 
been  very  improperly  confounded  with  encysted  tumours. 
Their  figure  is  round;  when  very  voluminous  they  push  up 
and  draw  away  the  skin,  and  are  then  pediculated  or  pyriform: 

*  See  Th.  Ch.  Bigot  Dissert,  sur  les  tumeurs  graisseuses  exterieur  au  pe~ 
ritoine,  etc. — Paris,  1821. 


OP  THE  COMMON  ADIPOSE  TISSUE.  139 

they  have  been  found  weighing  from  forty  to  fifty  pounds. 
On  the  exterior  of  the  serous  membranes  their  figure  is  gene- 
rally ovoid,  one  of  their  extremities  being  attached  to  the 
membrane,  the  other  to  the  skin;  outside  the  peritoneum  this 
tumour  constitutes  the  fatty  hernia  or  liparocele.  The  struc- 
ture of  the  lipoma  is  analogous  to  that  of  the  fat;  the  vesicles, 
according  to  Munro,  having  the  same  volume  as  the  latter, 
being  only  more  numerous.  A  cellular  envelope  similar  to 
that  which  surrounds  the  muscles,  and  which  is  sometimes  so 
dense  as  to  approximate  it  to  the  fibrous  membranes  and  the 
cysts,  is  generally  found  round  the  tumour.  This  membrane 
contains  vessels  which  are  tolerably  apparent.  The  lipoma, 
outside  the  peritoneum,  when  opened,  sometimes  exhibits  the 
aspect  of  the  epiploon:  generally  speaking  however  these 
tumours  contain  fewer  vessels  than  others  of  the  same  volume. 

Authors  have  spoken  of  fatty  transformations  of  the  mucles. 
The  following  is  what  observation  has  taught  me  on  this  sub- 
ject. In  palsy  the  muscles  often  become  perfectly  white; 
their  fibres  diminish  in  volume  at  the  same  time,  and  as  this 
alteration  is  chiefly  observed  in  old  persons,  in  whom  the  fat 
is  most  abundant  internally  and  as  the  part  being  at  rest  aug- 
ments the  quantity  of  this  fluid,  there  results  a  fatty  appear- 
ance of  the  muscles  that  has  been  mistaken  for  a  true  fatty 
transformation.  But  their  proper  fibrine  is  still  to  be  found 
in  them,  by  submitting  them  to  the  action  of  alcohol,  or  of  an 
absorbant  paper — when  boiled  in  water  or  exposed  to  the  fire. 
There  is  then  merely  a  discolouration  of  the  muscles,  but  no 
fatty  transformation.  M.  Vauquelin  and  M.  Chevreul,  in  the 
analysis  they  made  of  these  muscles,  obtained  similar  results. 
Neither  does  this  fatty  transformation  exist  in  the  bones.  The 
marrow  which  occupies  their  interior  may  become  more  abun- 
dant. The  liver  is  sometimes  the  seat  of  a  fatty  transforma- 
tion that  has  not  been  sufficiently  examined. 

Inflammations  which  occur  in  regions  where  the  adipose 
tissue  is  very  abundant,  have  a  peculiar  tendency  to  terminate 
in  gangrene.  This  observation,  which  has  long  been  made 
upon  the  very  fat  animals,  such  as  hogs  and  sheep,  when  they 
are  stung,  is  equally  correct  as  relates  to  man,  in  whom  wounds 


140  GENERAL  ANATOMY. 

and  infiltrations — stercoraceous  or  urinary  ones  particularly — 
in  the  fatty  tissue,  are  followed  by  extensive  gangrene.  The 
very  small  proportion  of  living  parts  contained  in  the  adipose 
tissue  may  account  for  these  phenomena.  Something  analogous 
may  be  seen  in  hernia  epiploicoe:  if  considerable  masses  of 
epiploon  be  left  externally,  this  organ  becomes  gangrenous  on 
its  surface,  abundance  of  oil  flows  from  it,  and  when  in  conse- 
quence of  this,  its  volume  is  considerably  reduced,  there  re- 
mains a  mere  red  and  very  vascular  mushroom,  formed  by 
the  cellular  tissue  intermediate  to  the  fat  and  by  the  develop- 
ment of  the  vessels. 

Dr.  Traill,  of  Liverpool,  in  a  case  of  hepatitis,  found  in  the 
serum  of  the  blood  drawn  by  venesection,  a  remarkable  quan- 
tity of  oil,  nearly  two  parts  and  a  half  to  the  hundred  of  se- 
rum. The  cysts  of  the  ovary  frequently  contain  fat  mixed 
with  hair,  and  sometimes  teeth,  but  the  alteration  is  in  that 
case  very  complex,  and  this  is  not  the  place  to  speak  of  it. 
Biliary  calculi  are  sometimes  formed  of  a  fatty  matter  called 
cholesterine.  Stercoraceous  matters  sometimes,  also,  contain 
fatty  substances,  either  intermixed,  or  in  separate  masses. 
Ambergrease  is  a  fatty  substance  that  appears  to  come  from 
the  intestine  of  the  physeter  macrocephalus.  Certain  cysts 
of  the  genital  organs  and  some  hydroceles  occasionally  con- 
tain brilliant  particles  that  are  nothing  more  than  cholesterine. 
This  matter  is  also  found,  though  less  frequently,  in  morbid 
tissues  situated  in  other  regions.  The  tumours  called  me- 
liceris,  steatoma  and  atheroma,  which  are  considered  as  sub- 
cutaneous, Chap,  iii.,  contain  a  certain  proportion  of  fatty 
matter. 


ARTICLE  IT. 
OF  THE  MEDULLARY,  OR  ADIPOSE  TISSUE  OF  THE  BONES. 

§  170.  The  medullary  tissue  is  a  membranous,  vascular  and 
vesicular  tissue  contained  within  the  cavities  of  the  bones. 
It  has  received  the  names  of  marrow,  medullary  system,  me- 
dulla, meditullium,  by  a  comparison  with  the  pith  of  trees. 


OF  THE  MEDULLARY  TISSUE  OF  THE  BONES.  141 

§  171.  Duverney*  has  made  it  the  subject  of  several  ob- 
servations: Grutzmachert  and  IsenflamJ  have  given  detailed 
descriptions  of  it.  Every  osteologist,  and  all  those  who  have 
paid  attention  to  the  adipose  tissue,  have  also  occupied  them- 
selves with  the  medulla.  Havers, §  particularly,  has  well  de- 
scribed and  figured  its  vesicular  texture.  Albinus  has  a  beau- 
tiful plate  of  it  in  his  Jlnnotationes  Academicx,  the  vessels 
however  are  represented  too  large:  Mascagni  in  his  Prodromo 
has  also  given  a  good  figure  of  the  medulla. 

§  172.  The  marrow  occupies  the  great  medullary  cavity  of 
the  bodies  of  the  long  bones,  the  cellular  cavities  of  the  short 
ones,  of  the  extremities  of  the  long  bones,  the  thickness  of  the 
wide  bones,  and  even  the  pores  of  the  compact  subtance  of  the 
bones.  It  is  totally  deficient  in  the  sinuses  and  aerial  cells  of 
the  bones  of  the  cranium. 

§173.  Thefatwhich  occupies  the  medullary  canal  of  thebones 
represents  a  cylinder  moulded  by  the  bony  parietes  of  this  ca- 
nal, and  is  contained  in  a  membrane  called  the  internal  or  medul- 
lary periosteum.  This  membrane,  whose  very  existence  some 
have  denied,  while  others  considered  it  as  being  formed  of 
two  layers,  is  composed  of  one  single  leaf,  easily  perceived 
by  an  experiment,  which  consists  in  sawing  a  bone  and  ex- 
posing it  to  fire  or  plunging  it  in  acid  :  the  membrane  becomes 
crisp,  is  detached  from  the  bone  and  forms  a  distinct  canal 
whose  tenuity  is  such,  that  without  this  precaution  it  is  almost 
impossible  to  see  it.  Its  tissue  can  only  be  compared  to  that 
of  a  cobweb.  This  membrane  lines  the  interior  of  the  bone 
and  appears  to  continue  on  to  their  extremities  with  the  mar- 
row that  fills  them.  It  sends  off  prolongations  into  the  com- 
pact substance  and  furnishes  inside  an  infinitude  of  similar 
parts,  whose  disposition,  in  general,  resembles  that  of  the 
filaments  and  lamina  that  compose  the  cellular  membranes. 

*  Memoires  de  PJlcademie  des  Sciences,  1700. 

•j-  De  ossium  medulla. — Lips.  1754. 

t  Ueber  das  Knockenmark,  in  beitrsege,  &e.  Von  Isenflamm  und  Rosen- 
muller — B.  II.,  Leipzig-,  1803. 

§  Clopton  Havers.  OsteoL  Nov. — Lond.  1691.  et  Obs.  nov.  de  ossibut. — 
Amstel.  1731. 


142  GENERAL  ANATOMY. 

These  prolongations  are  supported  by  the  filaments  and  lamina 
of  the  reticular  substance,  in  those  places  where  it  exists. 

§  174.  The  composition  of  the  medullary  membrane,  is  prin- 
cipally owing  to  the  vessels  that  are  ramified  in  the  interior  of 
the  canal,  and  which  are  supported  by  an  extremely  soft  and 
hardly  visible  tissue  :  this  membrane,  in  this  respect,  greatly 
resembles  the  pia-mater  or  the  epiploon,  and  appears  formed 
like  them,  by  the  cellular  tissue  belonging  to  the  sheaths  of 
the  vessels.  An  artery  and  vein  penetrate  into  the  medullary 
canal,  and  as  soon  as  they  have  entered  it,  divide  in  two 
branches,  whose  ramifications  extend  to  the  two  extremities 
of  the  bones,  and  communicate  with  the  numerous  and  large 
vessels  of  their  extremities.  The  lymphatic  vessels  have  been 
followed  to  the  entrance  of  the  medullary  cavities  only.  Suc- 
cessful injections,  on  the  contrary,  show  a  multitude  of  colour- 
ed filaments  in  the  canal  of  long  bones.  The  nerves  of  this 
canal,  whose  existence  has  been  denied,  may  be  easily  traced. 
Soemmering,  it  is  true,  thinks  that  these  nerves  are  destined 
for  the  artery  only.  These  nerves  have  been  particularly 
studied  by  Wrisburg  and  Klint.  The  medullary  tissue  is  then 
essentially  composed,  1st,  of  an  arterial  and  veinous  net-work, 
and  probably  of  one  of  lymphatic  vessels  also:  2d,  of  a  nervous 
plexus  destined  either  for  the  artery,  or  the  artery  and  other 
parts;  3d,  of  the  cellular  sheaths  peculiar  to  these  parts  that 
give  out  fibrilli,  whose  re-union  form  a  sort  of  incomplete, 
fringed,  membrane.  To  this  must  be  added  vesicles,  that  are 
very  apparent,  but  in  the  recent  subject  only,  as  in  others  they 
become  much  less  distinct,  owing  to  the  rapidity  with  which 
the  marrow  becomes  fluid.  These  vesicles  are  in  every  re- 
spect precisely  similar  to  those  of  the  adipose  tissue  in  gene- 
ral; they  have  the  same  volume,  and  the  same  connexion  with 
the  blood-vessels,  to  which  they  appear  appended.  Grutzma- 
cher,  thinks  that  the  texture  of  the  marrow,  and  that  of  the  fat 
generally,  is  areolar  like  the  common  cellular  tissue,  and  not 
vesicular.  The  spongy  extremities  of  the  long  bones  contain 
a  great  number  of  vessels;  but  their  membrane  is  less  dis- 
tinct than  that  of  the  middle  of  the  same  bones.  There  ap- 
pears to  be  vesicles  there,  similar  to  those  of  the  medullary 


OF  THE   MEDULLARY  TISSUE  OF  THE  BONES.  143 

membrane.     The  pores  of  the  compact  substance  appear  to 
contain  them  also. 

§  175.  The  fat  of  the  bones  is  called  marrow,  in  the  medul- 
lary canal,  medullary  fluid,  in  the  spongy  substance,  and  oily 
juice  in  the  compact  substance.  This  fat  is  formed  of  the  same 
elements  as  all  other  fat,  varying,  however,  in  the  propor- 
tions, being  more  fluid ;  it  is  also  more  highly  coloured  and 
yellower. 

§  176  The  medullary  membrane  is  sensible.  Duverney  has 
well  pointed  out  the  experiment,  which  proves  this  property, 
that  Bichat  has,  perhaps,  exaggerated  a  little,  but  which  it  is 
wrong  to  question.  If,  in  fact,  in  the  generality  of  the  amputa- 
tions performed  upon  man,  the  impression  caused  by  dividing 
the  bone  is  hardly  felt,  it  is  owing  solely  to  the  more  violent 
pain,  resulting  from  the  section  of  the  skin  which  has  preceded 
it.  But  if  in  a  living  animal,  we  allow  a  sufficient  interval  to 
elapse  between  the  section  of  the  teguments,  and  the  lesion  of 
the  marrow,  so  that  the  impression  produced  by  the  first,  may 
have  time  to  be  dissipated,  a  stylet  introduced  into  the  medul- 
lary canal,  produces  a  pain  on  the  instant,  which  is  testified  by 
the  animal  in  various  ways;  it  will  easily  be  supposed,  that 
this  sensibility  resides  in  the  membrane,  and  is  foreign  to  the 
marrow  itself.  The  nerves  in  the  bone  accompanying  the  prin- 
cipal medullary  artery,  if  the  bone  is  amputated  above  the  en- 
trance of  this  vessel,  the  remaining  marrow  no  longer  has  any 
communication  with  the  nervous  centre;  it  is  to  this  disposi- 
tion that  is  attributable,  the  difference  of  sensibility  observed 
by  Bichat,  between  the  centre,  and  the  extremities  of  the  me- 
dullary cavity,  and  also  to  the  fact,  that  the  nervous  threads 
proceed  in  dividing  themselves  towards  the  two  ends  of  this 
cavity.  The  medullary  tissue  is  gifted  with  an  obscure  con- 
tractility, similar  to  that  of  the  cellular  tissue.  The  arteries, 
which  ramify  in  this  membrane,  secrete  and  deposite  the  fat. 

§  177.  The  medullary  membrane,  according  to  Bichat,  has 
an  early  origin,  pre-existent  to  the  canal,  it  is  filled  with  a  car- 
tilaginous substance,  which  afterwards  gives  place  to  the  mar- 
row, as  fast  as  ossification  advances.  The  most  attentive  ob- 
servation has  discovered  no  arteries,  veins,  nor  medullary 
20 


144  GENERAL  ANATOMY. 

membrane,  in  the  cartilages:  at  a  later  period,  the  cavity  of 
the  large  bones  is  merely  a  narrow  canal  filled  by  the  artery; 
when  the  canal  begins  to  enlarge,  the  artery  throws  itself  on 
the  side,  and  fastens  itself  to  the  parietes;  a  viscid  or  gelatinous 
substance  is  then  contained  in  the  canal;  marrow  is  finally  pro- 
duced in  it,  but  in  small  quantities ;  in  time,  the  canal  increases 
in  size,  and  the  marrow  becomes  more  abundant.  As  respects 
this  tissue,  there  is  no  perceptible  difference  between  the 
sexes.  This  fluid,  presents  individual  differences  as  relates  to 
quantity.  In  a  state  of  ordinary  plumpness,  fat  forms  the 
greater  part  of  the  substance  contained  in  the  medullary  canal. 
In  eight  parts  of  this  substance,  I  have  found  seven  of  fat :  the 
remainder  is  formed  by  the  vessels,  water  and  albumen.  In 
lean  subjects,  on  the  contrary,  the  fat  constitutes  only  a  fourth, 
or  even  a  less  proportion  of  the  fluid  contained  in  the  long 
bones :  the  remainder  appears  to  me  to  be  water,  or  at  any  rate 
an  evaporable  substance,  and  albumen,  or  a  coagulable  sub- 
stance. According  to  Camper,  there  is  air,  instead  of  marrow 
in  the  cavities  of  the  long  bones  of  birds. 

§  178.  The  functions  of  the  medullary  tissue,  are  to  serve  as 
an  internal  periosteum,  and  as  a  reservoir  for  the  fat:  it  is  upon 
it  that  those  vessels  ramify,  which  are  directed  outwards  on 
the  one  hand,  to  assist  in  nourishing  the  bone,  and  inwards, 
on  the  other,  to  produce  the  secretion  of  the  fat.  The  latter, 
has  the  same  uses  as  in  other  parts.  Its  local  use  is  to  fill  up 
those  spaces  which  without  it  would  exist  in  the  bones.  It 
has  been  thought,  and  Haller  and  Blumenbach  were  of  the 
opinion,  that  it  rendered  the  latter  more  flexible,  and  less  fran- 
gible; but  the  bones  of  children,  deprived  of  fat,  are,  however, 
less  frangible  than  those  of  adults,  while  the  bones  of  old  peo- 
ple, in  whom  this  fluid  is  so  very  abundant,  are  in  general  very 
fragile.  Those  who  have  advanced  this  opinion,  found  it  upon 
the  fact,  that  combustion  deprives  the  bony  substance  of  all  its 
solidity;  it  is  evident,  however,  that  in  this  case  it  is  not  the 
oil  only  which  it  loses,  but  the  animal  matter  also,  on  which 
depended  their  solidity.  The  same  authors  add,  that  by  boil- 
ing the  earthy  residuum,  obtained  by  the  combustion,  in  oil 
or  gelatine,  its  solidity,  to  a  certain  degree,  is  restored;  but  a 


OP  THE  MEDULLARY  TISSUE  OP  THE  BONES.  145 

peculiar  compound  is  thus  formed,  a  kind  of  stucco*  that  has 
no  resemblance  to  bone.  Haller  and  other  physiologists  have 
also  thought  that  the  marrow  served  for  the  reproduction  of 
bone,  and  the  formation  of  callus  particularly.  Observation, 
however,  shows  us,  that  fractures  heal  so  much  the  more 
readily  as  the  patient  is  young,  and  the  less  marrow  there  is, 
or  the  less  fat  the  marrow  contains.  Duverney,  and  others, 
have  considered  the  marrow  as  necessary  to  the  nutrition  of 
the  bones;  is  a  sufficient  proof  of  the  inadmissibility  of  this 
opinion,  that  many  animals  have  none,  as  birds,  and  that  deer's 
horns  are  deprived  of  it,  that  this  fluid  does  not  exist  in  in- 
fancy, and  that  the  bones  are  formed  before  the  marrow.  The 
marrow  has  also  been  regarded  as  the  reservoir  of  latent  calo- 
ric, and  of  electricity.  Marrow  does  not  serve  to  lubricate 
articulating  surfaces,  for  the  synovia  exists  in  many  places 
where  there  is  no  marrow. 

§  179.  The  marrow  undergoes  some  morbid  changes.* 
While  the  bone  is  consolidating  in  fractures,  the  fat  disappears 
in  the  medullary  canal;  the  cellular  tissue  of  this  canal  becomes 
compact,  as  in  other  cases  of  solution  of  continuity,  and  ends 
in  ossification :  this  last  fact,  observed  by  Bichat,  has  since  been 
verified  by  several  observers,  when  the  consolidation  is  per- 
fect, the  medullary  membrane  re-assumes  its  properties. 

After  amputation,  the  same  phenomena  are  observed  in  the 
marrow,  as  in  other  wounds,  affecting  the  fatty  tissue  :  the  oily 
matter  disappears,  and  a  cellular  and  vascular  layer  is  formed 
at  the  truncated  extremity  of  the  bone  which  finally  closes. 
The  marrow  is  destroyed  in  the  sequestra,  and  does  not  appear 
to  be  re-established  after  they  are  taken  out;  at  least  it  has  ne- 
ver been  known  so  to  do;  perhaps  the  state  of  the  parts  has 
never  been  examined  a  sufficient  length  of  time  after  the  ter- 
mination of  the  disease. 

The  medullary  membrane  is  susceptible  of  inflammation: 
it  is  probable  to  this  and  its  consequences,  that  internal  necro- 
sis is  to  be  attributed.  It  is  equally  probable,  that  pains  in  the 
bones  depend  on  this  inflammation.  A  peculiar  induration  of 

*  See  Moignon.    Teutamen  de  morbis  ossium  medullas.    Paris  et  Lugtf. 
Ann.  iii. 


146  GENERAL  ANATOMY. 

the  medullary  membrane  is  observable  in  rachitis  which  has 
not  been  described. 

Among  the  affections  peculiar  to  this  membrane,  spina  ven- 
tosa  is  the  most  remarkable.  According  to  my  own  observa- 
tions and  those  of  several  others,  there  are  two  and  even  three 
distinct  species  of  this  disease.  The  considerable  develop- 
ment of  the  bone  arises  from  the  extraordinary  growth  of  the 
altered  medullary  membrane;  but  at  one  time  the  alteration 
in  the  marrow  consists  in  a  carcinomatous  degeneration  in  a 
true,  soft  cancer;  at  another  the  tumour  is  fibrous  and  carti- 
laginous: in  some  cases,  particularly  in  children,  the  bone 
enlarged  in  the  middle,  contains  a  highly  vascular  red  sub- 
stance whose  nature  has  not  been  well  determined  this  variety 
is  particularly  observed  in  the  bones  of  the  metacarpus,  of  the 
metatarsus  and  of  the  fingers.  Spina  ventosa  particularly  affects 
the  long  bones  of  the  limbs:  in  the  femur  it  is  generally  the 
inferior  part  of  the  bone  that  is  diseased,  in  the  humerus,  the 
superior.  I  have  taken  away  the  superior  third  of  the  fibula 
in  a  young  woman,  in  a  case  of  spina  ventosa,  that  had  en- 
larged the  head  of  the  bone  to  the  size  of  the  patient's  fist. 
Tumours  of  this  nature  have  been  described  by  Vignarous 
under  the  name  of  bony  steatoma,  and  by  Sir  A.  Cooper  under 
that  of  medullary  exostosis. 


OP  THE  SEROUS  MEMBRANES.  147 


CHAPTER  II. 


OF  THE  SEROUS  MEMBRANES. 

§  180.  The  membranes,  membranae,  are  soft,  broad  and  thin 
parts  that  line  the  cavities,  envelop  the  organs,  enter  into  the 
composition  of  a  great  number  of  them  and  constitute  others: 
they  differ  greatly  from  each  other  in  their  texture,  composi- 
tion, action,  &c. 

§  181.  The  serous  membranes,  membranx  serosse,  vel  suc- 
cingentes,  so  called  because  they  contain  a  great  many  serous 
vessels  in  their  thickness,  are  humected  by  a  liquid  analogous  to 
the  serum  of  the  blood,  and  because  they  furnish  tunicks  to  many 
organs,  form  a  system  or  numerous  genus  of  membranes  closed 
on  all  sides,  adhering  by  one  surface  to  the  surrounding  parts, 
loose  and  contiguous  to  themselves  on  the  other,  serving  to 
isolate  certain  parts,  to  facilitate  their  movements,  and  result- 
ing from  a  very  simple  modification  of  the  cellular  tissue. 

§  182.  Confounded  for  a  long  time  with  the  parts  to  which 
they  are  attached,  the  serous  membranes  have  been  particularly 
distinguished  from  other  parts  and  studied  in  their  ensemble 
by  Bonn,*  by  Munro,t  and  particularly  by  Bichat.J 

§  183.  The  serous  system  comprehends  membranes  which, 
by  their  numerous  points  of  similarity,  form  a  very  natural 
genus,  in  which,  however,  there  are  sufficient  differences  to 
mark  several  divisions  expedient.  In  relation  to  their  situa- 
tion, and  to  the  more  or  less  unctuous  liquid  which  humects 
them,  they  are  divided  into  serous  membranes,  properly  so 
called,  or  serous  membranes  of  the  splanchnic  cavities,  and 
synovial ;  the  latter  are  again  divided  into  those  of  the  articula- 

*  Be  continuationibus  mtmbmnarum.     Amst.     Batav.  1763. 
\  .7  description  of  all  the  bursae  mucosse,  6?c      Edinb.  1788. 
t  Traite  des  Membranes.     Paris,  an.  viii. 


148  GENERAL  ANATOMY. 

tions,  those  of  the  tendons  and  those  which  are  subcutaneous. 
We  must  first  examine  the  characters  common  to  all  the  genus, 
and  then  those  of  the  species. 


SECTION  I. 

OF  THE  SEROUS  MEMBRANES  IN  GENERAL. 

§  184.  All  these  membranes  consist  of  bladders  closed  on  all 
sides:  there  is  no  other  exception  to  this  general  disposition, 
than  the  opening  by  which  the  peritoneum  communicates 
with  the  genital  organs  in  women,  the  continuity  of  these  or- 
gans themselves  being  interrupted  between  the  ovary  and  the 
commencement  of  the  oviduct  or  fallopian  tube.  The  result 
of  the  general  conformation  of  the  serous  membranes,  is,  that 
the  fluids  they  contain  are  entirely  isolated,  and  that  their 
membranes  are  only  permeable  by  the  vessels  that  ramify  in 
their  thickness,  and  not  like  the  cellular  tissue,  by  areolae  freely 
communicating  with  each  other;  this  conformation  presents, 
however,  some  secondary  forms  or  varieties.  Some  of  these 
membranes  which  are  as  simple  as  possible,  resemble  an  am- 
pulla or  bladder;  they  are  called  vesicular.  Others  constitute 
sheathing  envelopes  that  surround  certain  parts  such  as  the 
tendons,  ligaments  and  the  blood  vessels;  and  as  they  are  not 
pierced  so  as  to  allow  these  parts  to  pass,  but  are  reflected  at 
their  two  extremities  and  so  form  a  double  sheath,  they  have 
received  the  appellation  of  vaginiform.  This  disposition  is 
one  of  the  most  usual.  There  are  some  however  that  are  still 
more  complex;  they  are  the  enveloping  serous  membranes, 
those  which  more  particularly  merit  the  name  of  succingentes: 
these  latter  surround  the  organs  except  at  one  single  point  of 
their  surface,  about  which  they  are  reflected  on  to  the  parities 
of  the  cavity  which  contains  them,  and  are  thus  divided  in 
two  portions,  of  which  one  forms  an  envelope  for  the  organs, 
and  is  called  the  visceral  layer,  or  tunic,  while  the  other 
which  lines  the  parietes,  constitutes  the  parietal  layer.  The 


OF  THE  SEROUS  MEMBRANES  in  GENERAL.       149 

different  forms  we  have  just  examined,  are  often  united  in 
the  same  membrane.  In  the  enveloping  serous  membranes, 
like  in  those  which  are  found  about  the  heart,  lungs  and  testi- 
cles, there  is  always  a  spot  on  the  surface  of  the  organ  deprived 
of  this  serous  envelope;  it  is  through  this  spot  that  the  vessels  of 
the  organs  penetrate,  or  that  the  organ  itself  is  attached  to  the 
surrounding  parts.  This  part,  freed  from  organs  covered  with 
serous  membranes,  is  sometimes  considerable,  at  others,  very 
narrow.  In  some  instances  the  viscus  is  removed  from  the 
parietes  which  contain  it,  arid  is  attached  or  suspended  by  a 
fold  of  the  serous  membrane  which  forms  what  is  called  a 
bridle  or  membranous  ligament:  this  disposition  is  no  excep- 
ception  to  what  we  have  just  said.  There  is  always  a  part  of 
the  organ,  not  covered  by'  the  membrane  throughout  the  whole 
extent  of  the  surface  to  which  the  fold  formed  by  the  latter 
adheres.  Besides  this  first  kind  of  folds  or  plaits,  the  serous 
membranes  present  prolongations,  that  float  more  or  less  loose- 
ly in  the  cavity  they  form,  and  which  most  commonly  depend 
on  their  visceral  layer,  but  which  sometimes  belong  to  the 
others :  the  epiploon,  the  appendicoe  epiploicoe  for  the  perito- 
neum; the  fatty  plaits  observed  in  the  pleura  on  the  sides  of 
the  mediastinum,  for  this  latter  membrane;  thesy  no  vial  fringes 
for  the  articulating  capsules,  are  all  examples  of  these  pro- 
longations. These  latter  always  contain  cellular  tissue,  gene- 
rally fatty,  within  their  substance:  it  is  here  also  that  the 
membrane  presents  most  vessels. 

§  185.  All  the  serous  membranes  have  two  surfaces,  one 
free,  the  other  adherent.  The  latter  is  flaky,  and  holds  to  the 
cellular  tissue,  to  ligaments,  tendons,  cartilages,  &c.  Its  de- 
gree of  adherence  to  these  different  parts  is  more  or  less  great: 
a  loose  cellular  tissue  sometimes  produces  it,  while  elsewhere 
as  on  the  cartilages,  it  adheres  closely.  There  is  a  multitude 
of  intermediate  degrees  between  these  two  extremes,  as  may 
be  observed  when  adhering  to  ligaments,  muscular  fibres, 
tendons,  &c.  The  free  surface  of  the  serous  membranes  is 
everywhere  contiguous  to  itself:  it  is  the  interior  of  a  kind 
of  bladder  that  these  membranes  resemble.  This  surface,  at 
the  first  glance,  appears  perfectly  smooth  and  polished:  but 


150  GENERAL  ANATOMY. 

microscopically  examined,  it  presents  manifest  villosities:  for 
this  reason  they  have  been  styled,  the  simple  villous  mem- 
branes. This  surface  is  constantly  humected  by  a  liquid. 

§  186.  The  serous  membranes  are  generally  of  a  whitish 
colour,  which  their  transparency  renders  scarcely  sensibler 
glistening  on  their  free  surface,  extremely  thin  yet  tolerably 
strong,  more  so  in  fact  than  the  cellular  tissue  would  be  if  re- 
duced into  lamina  of  an  equal  tenuity;  they  are  commonly 
slightly  elastic. 

§  187.  They  appear,  at  first  sight  nearly  homogeneous:  al- 
most always,  however,  a  fibrous  appearance,  more  or  less 
marked,  may  be  observed  in  various  parts  of  their  extent. 
When  torn  by  distension,  they  first  become  loosened,  and  then 
reduce  themselves  into  little  intermixed,  intercrossed,  and,  as 
it  were,  interwoven  filaments.  Their  nature  appears  very 
analogous  to  that  of  the  cellular  tissue,  from  which  they  only 
differ  by  their  greater  density  and  the  distinct  cavity  they 
represent.  Between  the  cellular  tissue  and  the  serous  mem- 
branes, there  exists  a  sort  of  insensible  gradation,  and  the  most 
simple  of  the  serous  membranes  still  partake  largely  of  the 
nature  of  the  cellular  tissue.  The  very  loose  cellular  tissue 
in  which  inflation  develops  large  ampulloe,  as  that  of  the  pre- 
puce, that  which  exists  between  the  great  moving  muscles 
and  the  subcutaneous  synovial  bursae,  constitute  a  transition 
between  the  two  tissues.  Very  numerous  white  vessels  enter 
into  the  composition  of  these  membranes.  Injections  and 
inflammation  penetrate  the  first  with  a  coloured  liquid;  the 
second,  the  blood,  in  these  vessels  render  the  latter  very  ap- 
parent: their  number  then  appears  very  considerable.  We 
must  not,  however,  confound  the  vessels  peculiar  to  the  serous 
membrane  with  those  that  belong  to  the  subjacent  cellular 
tissue,  and  which  might  be  supposed  to  exist  in  the  membrane 
itself,  on  account  of  its  transparency.  In  the  peritoneum,  for 
instance,  the  inflammation  must  last  for  a  long  time  to  cause 
the  blood  to  penetrate  beyond  the  sub-serous  cellular  tissue; 
and  on  a  slight  observation  one  would  be  tempted  to  think  it 
was  the  peritoneum  itself  rendered  vascular  by  the  disease.  It 
is  the  same  with  injections;  it  is  only  when  they  are  extreme- 


OF  THE  SEROUS  MEMBRANES  IN  GENERAL.  151 

ly  thin  that  they  penetrate  into  the  membrane  itself.  The 
nerves  of  the  serous  membranes  are  not  known. 

§  188.  The  liquid  contained  in  these  membranes  is  not  the 
same  in  all;  it  resembles  however  more  or  less  the  serum  of 
the  blood  or  blood  deprived  of  its  colouring  matter.  It  con- 
tains, in  general,  water,  albumen,  an  incoagulable  matter  that 
may  be  considered  a  sort  of  gelatiniform  mucus,  a  fibrous 
matter  and  soda.  We  shall  see  hereafter  the  difference  pre- 
sented by  this  liquid  in  the  various  species  of  the  serous 
membranes. 

§  189.  The  serous  membranes,  during  life  particularly,  are 
highly  extensible  and  retractile,  as  is  seen  in  dropsies  and 
after  the  disease  is  cured:  but  their  enlargement  is  not  always 
the  result  of  their  extensibility;  their  folds  disappear,  which 
being  gradually  developed,  serve  to  aid  the  increase  of  the 
membrane.  Another  cause  which  assists  in  this  augmenta- 
tion of  volume,  is  the  sliding  of  which  this  is  susceptible,  the 
species  of  locomotion  it  experiences  when  it  is  distended  in 
one  part  only,  as  is  particularly  seen  in  hernia.  There  appears 
also  in  some  cases  a  real  increase  of  nutrition,  which  contri- 
butes to  the  production  of  this  phenomena :  this  augmentation, 
with  the  other  causes  of  ampliation  is  manifested  in  pregnan- 
cy. These  phenomena  are  not  all  equally  marked  in  the 
different  species  of  serous  membranes:  the  peritoneum  pre- 
sents them  in  the  highest  degree;  they  are  much  less  so  in  the 
synovial  membranes,  the  articulating  ones  particularly,  which 
partly  arises  from  the  less  extensible  nature  of  these  mem- 
branes, and  from  their  having  fewer  folds,  and  above  all  from 
their  connexions  which  do  not  permit  them  to  displace  them- 
selves with  the  same  facility.  When  the  distension  has  ceased 
they  gradually  return  to  their  original  state,  but  if  it  has  pro- 
ceeded to  a  very  relaxed  state,  traces  of  it  always  remain. 

§  190.  The  force  of  formation,  tolerably  well  developed  in 
the  serous  membranes,  is  less  so  in  them,  however,  than  in  the 
free  cellular  tissue.  Their  mobility  is  very  limited,  extending 
only  to  the  feeble  degree  which  constitutes  tonicity.  But  if 
irritation  does  not  occasion  in  them  any  perceptible  move- 
ments, it  develops  sensibility  there:  in  fact  these  membranes 
21 


152  GENERAL  ANATOMY. 

become  very  sensible  and  generally,  in  inflammation  trans- 
mit painful  impressions. 

§  191.  All  the  serous  membranes  are  the  seat  of  the  constant 
deposition  and  absorption  of  a  serous  liquid  in  their  cavity  or  in 
their  free  and  contiguous  surface.  The  great  extent  of  these 
membranes,  taken  together,  gives  great  importance  to  this  dou- 
ble function.  The  matter  of  this  secretion,  like  all  the  others,  is 
brought  by  the  vessels  into  the  thickness  of  the  membrane, 
and  particularly  into  its  most  vascular  points,  the  fringed 
prolongations:  by  what  way  the  secreted  matter  leaves  the 
vessels  and  passes  into  the  cavity,  is  not  exactly  known.  Se- 
creting glands  have  been  supposed  for  all  these  membranes, 
either  in  their  vicinity  or  in  their  own  thickness — but  no  such 
glands  exist.  Transudation  by  organic  pores,  has  also  been 
supposed;  but  without  exactly  knowing  the  mode  in  which 
the  perspiratory  secretions  are  performed,  we  know  that  tran- 
sudation  takes  place  in  the  dead  body  only,  and  then  even 
some  time  after  death.  The  liquid  is  also  continually  absorbed 
by  the  membrane,  in  the  thickness  of  which  it  re-enters  the 
vessels.  While  the  deposition  and  absorption  remain  in  equi- 
librium, the  serous  membranes  are  simply  moistened  on  their 
surfaces.  The  augmentation  of  the  secretion  or  the  diminu- 
tion of  the  absorption,  gives  rise  to  an  accumulation  called 
dropsy. 

The  secreted  liquid  has  local  uses  and  general  uses:  locally, 
it  serves  to  preserve  the  separation  between  the  two  contiguous 
layers  of  the  serous  membranes  and  to  facilitate  the  motion 
of  the  organs  over  one  another;  generally,  it  is  probable,  that 
the  nutritious  matter  thus  alternately  deposited  and  taken  up 
becomes  more  perfectly  assimilated,  previous  to  its  employ- 
ment in  nourishing  the  organs. 

§  192.  The  action  of  the  serous  membranes,  in  health  and 
in  disease  particularly,  is  closely  united  with  those  of  the 
other  organs.  Thus,  when  they  are  diseased,  the  functions 
of  the  organs  they  invest  are  more  or  less  disturbed,  and  this 
disturbance  extends  to  a  distance,  and  often  to  the  whole  or- 
ganism; in  the  same  way,  affections  of  other  organs  particu- 
larly those  of  the  tegumentary  membranes,  of  the  circulating 


OF  THE  SEROUS  MEMBRANES  IN  GENERAL. 

organs,  and  of  the  glands,  frequently  derange  their  functions; 
the  affections  of  the  organs  they  invest  always  produce  a  cor- 
responding one  in  them,  more  or  less  evident;  on  the  one  hand, 
the  cavity  they  form  establishes  a  complete  isolation  between 
the  parts  on  which  their  opposite  portions  are  reflected;  on 
the  other,  the  continuity  and  extent  of  these  membranes,  easily 
give  rise  to  very  extensive  affections. 

§  193.  At  its  origin,  about  which  however  little  is  known, 
the  serous  system  is  very  soft:  in  the  embryo  the  abdominal 
viscera  seem  covered  with  a  mere  viscid  and  liquid  varnish. 
The  serous  membranes  are  very  thin  in  the  fretus,  and  in  ge- 
neral less  adhesive,  on  account  of  the  softness  of  the  cellular 
tissue  which  unites  them  to  the  neighbouring  parts,  so  that 
they  are  easily  separated  from  these  latter:  in  the  articulating 
cartilages,  however,  and  in  the  albuginea  of  the  testicle,  the 
adhesion  is  almost  as  great  as  at  a  later  period.  We  are  com- 
pletely ignorant  whether  or  not  these  membranes,  whose  essen- 
tial character  is  the  interruption  of  continuity  they  establish 
between  the  parts,  are  at  first  a  soft  cellular  tissue,  continuous 
and  without  an  internal  cavity,  as  is  affirmed  by  some  anato- 
mists, who  admit  that  in  the  beginning,  there  exists  a  general 
continuity  of  all  the  parts ;  among  the  bones,  for  instance.  The 
liquid  of  the  serous  membranes  is  at  first  very  thin;  some  of 
these  membranes,  those  of  the  splanchnic  cavities,  present  in 
the  foetus  remarkable  differences  of  conformation.  In  old  age 
the  serous  membranes  undergo  various  changes. 

§  194.  The  conformation  of  an  accidental  serous  tissue  is 
frequently  observed;  its  reparatation  or  reproduction  takes 
place  in  wounds  of  the  serous  membranes,  which  reunite  when 
their  edges  are  in  direct  contact;  observation  has  shown  the 
opinion  of  the  ancients,  who  did  not  believe  this  kind  of  wound 
susceptible  of  reunion,  to  be  totally  void  of  foundation.  When 
these  wounds  are  attended  with  loss  of  substance,  or  when 
there  is  a  separation  of  their  edges,  the  space  is  filled  up  by  a 
new  membrane,  a  true  cicatrix;  this  appears  a  little  thinner 
and  more  extensible  than  the  surrounding  membrane. 

§195.  The  liquid  contained  in  the  cavity  of  the  serous 
membranes  is  susceptible  of  accumulation  either  from  the  ab- 


154  GENERAL  ANATOMY. 

sorption  being  diminished  or  the  exhalation  being  increased: 
this  accumulation  produces  various  dropsies.  The  liquids 
formed  in  the  latter,  presents  various  qualities,  particularly  if 
there  is  inflammation.  This  fluid  sometimes  contains  more 
animal  matter  than  is  found  in  a  state  of  health,  at  others 
less:  sometimes  the  proportion  of  this  matter  is  the  same  as 
in  that  state.  Generally  speaking,  the  serosity  of  dropsies 
resembles  the  serum  of  the  blood,  except  in  having  a  less  pro- 
portion of  albumen.  There  is  one  point  of  pathological  ana- 
tomy to  which  sufficient  attention  has  not  been  paid;  that  is 
the  dropsies  which  do  not  appear  to  depend  upon  an  altera- 
tion of  the  serous  membranes  or  of  the  organs  of  respiration 
and  circulation,  and  which  for  this  reason  have  been  regarded 
as  general  affections,  are  often  preceded  and  accompanied  by 
a  flow  of  urine  containing  a  great  proportion  of  gelatine  and 
albumen,  a  substraction  of  animal  matters  which  alter  the 
composition  of  the  blood,  which  renders  it  more  watery  and 
which  is  owing  to  an  alteration  of  the  kidney  and  its  function. 
This  flux  sometimes  also  accompanies  dropsies  with  a  local 
affection  of  another  viscus.  * 

§  196.  Inflammation  of  the  serous  membranes,  which  is 
a  very  frequent  occurrence,  produces  in  these  membranes, 
changes  in  their  tissue  and  in  their  secretions.  The  membrane 
becomes  vascular  at  first  in  its  external  cellular  tissue,  and 
after  a  while  in  its  own  thickness;  its  vascular  fringes  and 
villosities  are  better  marked,  and  finally  become  more  promi- 
nent and  very  thick.  If  the  inflammation  continues  for  a  cer- 
tain time,  the  membrane  becomes  thickened  and  loses  its 
transparency;  this  thickening,  however,  which  appears  very 
great,  is  generally  in  appearance  only  and  is  foreign  to  the 
membrane  itself.  Besides  the  interstitial  arrangement  which 
gives  rise  to  this  alteration,  a  secretion  takes  place  in  the  ca- 
vity of  the  membrane  itself;  the  secretion  however,  is  at  first 
suspended,  afterwards  to  be  renewed  with  a  change  of  charac- 
ter. The  liquid  poured  out,  is,  as  the  case  may  be,  either  a 
simple  and  abundant  serum,  but  not  materially  altered,  or  a 

*  See  T.  Blackall,  Observations  on  Dropsies,  etc.  London,  1813. 


OF  THE  SEROUS  MEMBRANES  IN  GENERAL.  155 

whitish  lactescent  fluid,  or  containing  albuminous  and  fibrin- 
ous  flakes;  sometimes,  though  rarely,  the  serum  is  bloody; 
finally,  pus  is  to  be  found  in  it,  having  all  the  properties  of 
that  produced  in  the  cellular  tissue.  Besides  these  effects  of 
inflammation,  there  are  others  which  are  very  remarkable. 

§  197.  The  false  membranes,  the  pseudo  membranae,  are 
not  peculiar  to  the  serous  membranes,  but  are  frequently  found 
there.  They  consist  in  the  concretion,  under  the  form  of  a 
membrane,  of  the  product  of  the  secretion  of  the  membrane, 
inflamed  to  a  certain  extent.  This  product,  similar  to  the  or- 
ganizable  matter  which  determines  the  adhesion  of  the  lips  of 
wounds,  is  at  first  thrown  in  separate  drops  on  the  free  surface 
of  the  membrane;  these  drops,  by  their  multiplication  and 
extension,  generally  meet,  forming  first  a  net-work,  then  an 
entire  surface.  Most  commonly  the  same  thing  takes  place 
on  the  opposite  side  of  the  membrane  and  the  latter  generally 
remaining  in  contact  with  the  former,  the  false  membrane  oc- 
casions the  agglutination  of  the  two  parts,  previously  contigu- 
ous :  this  is  the  first  degree  of  adhesion,  the  gelatinous  adhe- 
sion of  some,  and  the  plastic  adhesion,  adherence  couenneuse 
of  others;  I  prefer  calling  it  agglutination.  At  one  time  the 
agglutinating  matter  merely  forms  a  thin  layer  interposed  be- 
tween the  approximated  surfaces,  at  another,  it  is  so  abundant, 
that  it  fills  and  distends  the  serous  cavity. 

Organic  adhesions  of  the  serous  membranes,  are  a  frequent 
result  of  the  formation  of  false  membranes.  The  organizable 
matter  of  the  agglutination,  is  converted  into  cellular  tissue, 
in  which  are  formed  ramifying  canals,  which  gradually  acquire 
the  vascular  structure,  (chap,  iv.)  and  which  end  by  commu- 
nicating with  the  vessels  of  the  inflamed  membrane.  Several 
of  the  first  observers,  who  saw  the  vessels  of  the  adhesions, 
mistook  them  for  vascular  villosities,  prolonged  from  the  old 
membrane  into  the  matter  of  the  false  one.  J.  Hunter  and 
M.  Ev.  Home,  have  observed  the  contrary,  a  fact,  the  truth 
of  which  I  have  several  times  proved.  By  pricking,  at  ran- 
dom, a  recent  adhesion  with  a  tube  filled  with  mercury,  we 
can  inject  the  ramifying  canals,  whose  largest  part  or  trunk, 
corresponds  with  the  centre  of  the  adhesion,  and  whose  branches 


156  GENERAL  ANATOMY. 

diverging  in  opposite  directions,  like  those  of  the  vena  porta, 
are  directed  towards  the  serous  surfaces,  without  always  ar- 
riving there,  and  without  the  latter  presenting  any  well  marked 
villosities.  In  time,  this  disposition  changes,  as  soon  as  the 
canals  have  communicated  with  the  old  vessels,  the  adhesion  be- 
comes more  and  more  vascular  in  the  vicinity  of  the  membrane, 
and  less  and  less  in  its  centre.  Organic  adhesions  of  the  serous 
membranes,  have  not  always  the  same  form,  they  consist,  gene- 
rally in  bridles  or  cords,  larger  at  the  adhering  extremities, 
and  smaller  in  the  centre  which  is  free;  at  other  times,  there  is 
a  great  number  of  filaments  nearly  similar  to  the  bridles;  in 
other  cases,  the  adhesions  are  so  multiplied,  that  the  two  parts 
of  the  membrane  are  confounded,  and  seem  to  be  replaced  by 
the  cellular  tissue.  The  texture  of  the  adhesions,  as  seen  in 
the  bridles,  is  that  of  the  serous  membranes ;  they  form  a  sort 
of  smooth  sheath,  filled  with  cellular  tissue  containing  some 
vessels.  These  adhesions  are  on  the  one  hand  so  frequent, 
and  on  the  other  so  regularly  organized,  that  many  of  the  an- 
cient physicians  took  them  for  natural  ligaments,  and  that 
among  the  moderns,  Tioch  has  found  some  of  them  in  the 
pericardium,  and  Bichat  in  the  pleura,  that  appeared  to  them 
to  belong  to  an  original  conformation. 

The  bridles  or  bands  which  form  the  adhesions,  lengthen  as 
they  harden, it  is  even  probable  that  in  the  end,  their  centres  are 
completely  absorbed;  what  inclines  us  to  this  belief,  is,  that  in 
examining  the  parietes  of  the  abdomen,  soon  after  wounds  of 
this  part,  we  generally  find  the  intestine  adhering  to  the  place 
of  the  wound,  while  at  a  more  distant  period,  the  adhesion  is 
merely  formed  by  a  bridle,  which  at  last  becomes  itself  very 
thin;  and  finally,  that  if  we  observe  the  disposition  of  the  parts, 
at  the  end  of  a  very  long  period,  we  find  no  adhesion  what- 
ever. These  different  degrees,  were  all  found  in  the  body  of 
a  patient,  I  dissected,  who  was  affected  with  melancholy,  and 
who  had  stabbed  himself  with  a  knife  twelve  or  fifteen  times, 
at  different  periods  of  his  life. 

§  198.  The  serous  membranes  undergo  several  transforma- 
tions, or  to  speak  more  correctly,  are  the  seat  of  various  acci- 
dental productions.  Fibrous,  cartilaginous,  fibre-cartilaginous. 


OF  THE  SEROUS  MEMBRANES  IN  GENERAL.       157 

and  even  bony  plates,  are  frequently  observed  in  their  thick- 
ness, particularly  in  the  pleura,  which  sometimes  forms  a  sort 
of  shield  in  consequence  of  chronic  pleurisy.  These  plates, 
are  generally,  it  is  true,  subjacent  to,  or  laid  over  them. 

Free  or  pediculated  concretions  have  their  seat  in  the  inte- 
rior of  these  membranes.  They  are  found,  more  particularly, 
in  the  articulating  serous  membranes,  sometimes,  however,  in 
those  of  the  tendons,  and  even  in  the  splanchnic  cavities.  They 
are  at  first  external  to  the  membrane,  and  afterwards  pushing 
it  gradually  before  them,  they  project  into  its  interior,  where 
they  present  a  wide  and  short  base,  and  at  a  later  period,  a 
pedicle  which  becomes  longer  and  longer,  until  finally  break- 
ing, they  become  perfectly  free  in  the  cavity  of  the  mem- 
brane. Such  is  the  true  mechanism  of  the  formation  of  these 
bodies,  that  have  been  taken  for  true  concretions,  when  they 
had  not  been  observed  in  their  different  stages  of  development. 
The  consistence  of  these  bodies  varies:  sometimes  they  are 
very  soft  and  albuminous,but  most  commonly  they  are  fibrous, 
cartilaginous  or  bony. 

The  serous  membranes  participate  in  the  degenerations 
common  to  all  the  tissues;  they  appear,  also,  to  be  subject  to 
some  that  are  peculiar  to  them. 

§  199.  Vices  of  conformation  are  to  be  observed  in  some  of 
these  membranes,  as  in  the  arachnoid  membrane  of  the  anen- 
cephalous  foetus,  in  the  peritoneum  and  vaginal  tunick,  when 
the  canal  of  communication  between  these  two  membranous 
sacs  subsists  after  birth.  A  kind  of  supernumerary  sacs  have 
been  found  in  the  peritoneum:  Neubauer  gives  some  examples. 
Acquired  vices  of  conformation  are  also  peculiar  to  a  small 
number  of  these  membranes,  and  belong  to  special  anatomy. 
Hernia  is  one  of  these  vices. 

§  200.  Cysts  may  with  propriety  be  described  along  with 
the  serous  membranes:  it  is  in  fact  with  this  genus  of  organs 
that  they  have  the  greatest  resemblance.  They  resemble,  in 
general,  like  all  the  parts  comprised  in  the  serous  system,  a 
pocket  or  membranous  cavity,  closed  on  all  sides,  adherent  on 
one  surface,  free  on  the  other,  and  in  contact  with  a  liquid 
which  fills  it:  they  are  commonly  of  a  globular  form;  their 


1  58  GENERAL  ANATOMY. 

volume  varies  from  that  of  a  grain  of  millet  to  that  of  the  dis- 
tended abdomen;  here  we  find  them  isolated,  and  there  several 
grouped  together  and  communicating  with  each  other;  their 
external  surface  is  floculent,  cellular,  sometimes  having  laminae, 
or  even  a  fibrous  layer;  sometimes  this  surface  is  lined  with  a 
natural  membrane  which  they  have  encroached  upon  in  sally- 
ing towards  a  surface;  their  internal  surface  is  smooth  and 
polished:  the  thickness  varies,  and  is  in  general  less  in  the 
cysts  of  the  organs,  than  in  those  of  the  free  cellular  tissue;  it 
is  also  greater  or  less  in  different  parts  of  the  same  cyst;  the 
consistence  varies  from  that  of  a  barely  concrete  liquid,  to  that 
of  the  serous  and  even  of  the  fibrous  tissue;  it  is  the  same  with 
their  adhesions  which  are  sometimes  very  close,  and  at  others 
seem  to  be  a  simple  agglutination:  there  are  no  apparent  ves- 
sels on  their  free  surface. 

The  liquid  they  contain  is  not  less  various.  At  one  time, 
we  find  it  a  serum,  either  limpid  or  more  or  less  thick  like 
albumen,  variously  coloured;  at  another  it  is  fat,  either  fluid, 
or  in  particles  forming  cholesterine;  in  some  cases  it  is  mucus 
or  a  viscid  substance,  which,  instead  of  coagulating  by  heat, 
evaporates  almost  wholly,  leaving  but  very  little  residuum; 
in  others  it  is  a  mixture  of  mucus  and  albumen,  or  a  blackish 
matter  resembling  chocolate,  sometimes  even  pure  blood;  at 
others  hydatid  worms;  sometimes  crystallized  saline  sub- 
stances :  a  concrete  substance  has  also  been  found  there,  re- 
sembling caoutchouc. 

The  cysts  are  in  a  state  of  repletion  that  may  be  compared 
to  the  dropsies  of  the  serous  membranes :  they  are  the  seat, 
however,  of  a  continual  secretion  and  absorption ;  they  disap- 
pear in  certain  cases,  persist  in  some,  and  continually  increase 
in  others. 

Different  theories  have  been  proposed  to  explain  the  forma- 
tion of  cysts.  Some  authors  regard  them  as  membranes  of  a 
new  formation  which  are  developed  round  an  originally  exist- 
ing substance;  others  again,  on  the  contrary,  think  they  are 
pre-existent  to  the  matters  they  contain,  whether  they  be  form- 
ed by  the  distended  cellular  tissue,  or  owe  their  production  to 
the  dilated  lymphatics.  It  is  difficult  to  say,  exactly,  which  of 


OF  THE  SEROUS  MEMBRANES  IN  GENERAL.       159 

the  two  opinions  are  right.     There  are  cases  that  favour  each 
of  them.     Certain  tissues  that  are  classed  with  the  cysts,  arc 
evidently  pre-existent.     In  this  class  we  may  place  the  sub- 
cutaneous wens,  which  are  nothing  more  than  sebaceous  folli- 
cles, considerably  enlarged,  and  not  accidental  sacs,  the  cysts 
of  the  ovary,  which  appear  to  depend  upon  the  extraordinary 
development  of  the  vesicles  of  that  organ,  the  cysts  of  the  testi- 
cular  cord  of  man,  or  of  the  labia  pudendi  of  woman,  which  are 
the  remains  of  the  tunica  vaginalis,  &c.     Another  genus  of 
cysts,  are,  on  the  contrary,  formed  consecutively;  such  are 
those  which  follow  the  effusion  of  blood  which  occur  in  the 
brain,  those  which  are  developed  around  a  foreign  body,  &c. 
In  other  cases  it  is  very  difficult  to  determine  the  mode  and 
origin  of  cysts.     It  is  very  likely,  however,  that  all  true  cysts 
are  membranes  of  a  new  formation,  determined  or  not  by  an 
evident  inflammation.    The  cysts  are,  besides,  subject  to  all  the 
affections  of  the  serous  membranes,  to  all  the  varieties  of  in- 
flammation, to  accidental  productions  either  analogous  or  mor- 
bid.    They  have  been  found  every  where,  in  bones  and  car- 
tilages, perhaps,  excepted. 

The  new  cellular  membranes,  which  envelop  accidental, 
analogous,  or  morbid  accidental  productions,  and  foreign  bo- 
dies, are  generally  confounded  with  cysts.  These  envelopes 
are  not  like  the  cysts  and  the  serous  membranes,  inhalant  and 
exhalant  surfaces:  they  often  line  the  cysts.  Their  consistence 
varies  :  they  are  also  always  parts  of  a  new  formation. 

Between  the  cysts  or  serous  vesicles,  holding  to  the  cellular 
tissue  by  their  external  surface,  and  the  hydatids,  there  are 
insensible  transitions,  between  which  it  is  very  difficult  to 
draw  a  well  denned  line  of  demarcation.  Thus  the  little  se- 
rous vesicles,  that  are  so  often  found  in  the  plexus  choroides, 
those  which  are  sometimes  seen  at  the  fringed  extremity  of 
the  fallopian  tubes ;  those  which  I  have  frequently  seen  in  the 
vegetation  of  the  nasal  and  uterine  mucous  membranes,  all  evi- 
dently appear  to  belong  to  the  cysts.  The  hydatid  or  cluster- 
ed mole  appears  to  me  to  belong  to  the  same  genus,  yet  a  very 
able  physician  and  naturalist,*  refers  it  to  the  genus  acephalo- 

*  See  li.  Cloquct.  Faune  des  medians,  torn.  i.  Paris  1822. 
22 


160  GENERAL  ANATOMY. 

cyst.  The  three  species  of  simple  acephalocysts  themselves, 
whose  animality  is  yet  doubtful,  approximate  in  a  certain  de- 
gree to  the  cysts.  I  have  taken  from  under  the  skin  of  the 
neck,  and  several  times  from  under  the  skin  of  the  mammae, 
acephalocysts  of  these  species  that  were  single,  not  encysted, 
not  adhering,  it  is  true,  but  agglutinated  to  the  cellular  tissue. 
Most  commonly  we  find  one  or  the  other  of  the  three  species 
of  simple  acephalocysts,  assembled  in  great  numbers  and  free, 
in  a  distinct  cyst. 

A  modern  physician*  has  attributed  the  origin  of  tubercles, 
of  all  tumours,  and  even  of  all  foreign  bodies  suspended  or  free 
in  the  serous  and  synovial  cavities,  to  the  formation,  develop- 
ment and  transformations  of  the  hydatids,  or  hydatiform  cysts 
of  which  we  have  been  speaking. 

After  having  given  the  general  history  of  the  serous  system, 
we  must  describe  in  succession  the  various  species  which  com- 
pose it. 


SECTION  II. 

ARTICLE  I. 
OF  THE  SUB-CUTANEOUS  SYNOVIAL  BURS.E. 

§201.  The  synovial  or  mucilaginous  sub-cutaneous  bursae, 
bursas  mucosas  sub-cutanese^  had  not  been  described  by  anato- 
mists. Some  pathologists,  and  particularly  Gooch,  Camper, 
and  lately  M.  Asselin,  have  spoken  of  their  dropsy,  and  while 
treating  of  this,  Camper  has  a  word  upon  their  healthy  state. 
I  have  examined  and  described  them  for  a  long  time  in  my  lec- 
tures; I  have  also  mentioned  them  in  the  additions  to  the  gene- 
ral anatomy  of  Bichat,  and  in  the  Dictionnaire  de  Medecin. 

§  202.  The  synovial  bursae,  whose  rudiments  are  partly  seen 
in  the  loose  and  very  extensible  cellular  tissue,  which  exists 
between  all  the  very  moveable  parts,  are  found  under  the 
skin,  wherever  that  membrane  covers  parts  that  exercise  great 

*  See  J.  Baron.  An  inquiry  &c.  on  tuberculous  diseases.  London,  1817. 


OP  THE  SUB-CUTANEOUS  SYNOVIAL  BURS.E.  161 

and  frequent  motions;  as  between  the  skin  and  the  patella,  the 
olecranon  and  the  skin,  on  the  trochanter,  on  the  acromion, 
before  the  thyroid  cartilage;  sometimes  behind  the  angle  of 
the  jaw;  always  between  the  skin  and  projecting  side  of  the 
metacarpal  and  metatarsal  articulations,  and  between  those  of 
the  first  and  second  phalanges.  All  these  latter  are  generally 
confounded  with  the  neighbouring  tendons. 

In  order  to  have  a  good  view  of  these  membranes,  we  must 
fill  them  with  air.  It  is  then  seen  that  they  form  an  obround, 
multilocular  cavity,  that  is,  a  cavity  divided  by  incomplete, 
but  closed  partitions,  the  air  blown  into  it,  remaining  shut  up 
there,  and  not  passing  into  the  surrounding  cellular  tissue;  the 
walls  of  the  cavity  they  form  are  very  thin  and  weak. 

Their  texture  is  very  simple,  like  those  of  the  serous  mem- 
branes generally,  and  appears  to  differ  from  that  of  the  cellular 
tissue,  only  by  a  little  greater  density.  There  are  but  very  few 
vessels  in  the  thickness  of  these  membranes:  their  free  and 
contiguous  surface  is  humected  by  an  unctuous  or  mucilagi- 
nous liquid,  in  such  small  quantities,  as  to  preclude  the  possi- 
bility of  its  being  properly  examined. 

The  local  use  of  these  membranes  and  the  unctuous  liquid 
they  contain,  is  evidently  to  facilitate  the  motion  of  the  bones 
under  the  skin. 

These  bursae  are  developed  at  a  very  early  period ;  they  exist 
at  the  time  of  birth,  and  are  then  easily  perceived  on  account 
of  the  greater  abundance  of  the  liquid  that  moistens  them. 

Their  development  augments  in  proportion  to  the  exercise 
of  the  parts  they  cover;  that  of  the  acromion,  for  instance,  be- 
comes more  apparent  in  individuals  who  carry  burdens  on  the 
shoulder;  that  of  the  knee  is  most  developed  in  those  who  are 
habitually  kneeling. 

§  203.  They  are  formed  accidentally,  in  those  cases  where 
the  skin  exercises  accidental  rubbings.  M.  Brodie  speaks  of 
a  gibbosity,  on  which  one  was  developed  in  consequence  of 
the  continued  sliding  of  the  skin:  the  same  thing  is  observable 
in  club-foot  in  the  spot  where  the  skin  rubs  against  the  salient 
side  of  the  tarsus;  and  again,  the  same  result  takes  place  after 


162  GENERAL  ANATOMY. 

amputation  of  the  thigh,  between  the  end  of  the  bone  and  the 
cicatrix. 

Dropsy  of  the  sub-cutaneous  synovial  bursae,  constitutes  hy- 
groma,  an  affection  known  to  the  ancients,  that  is  observed 
particularly  in  the  knee,  before  the  patella  of  persons  who  ha- 
bitually rest  on  it,  such  as  priests,  nuns,  the  washerwomen  of 
certain  countries,  servants  who  scrub  in  that  posture,  sweeps 
&c.  and  that  is  also  occasionally,  but  less  frequently  seen  in  the 
other  membranes  of  the  same  species.  Hygroma  may  acquire 
considerable  volume.  It  sometimes  suddenly  disappears  with- 
out any  known  cause,  or  after  medicinal  applications.  I  have 
sometimes  punctured  it,  and  withdrawn  a  viscid  serum.  A 
stimulating  injection,  after  the  fluid  is  abstracted,  often  pro- 
duces a  mutual  adhesion  of  the  walls,  and  an  obliteration  of  the 
cavity. 

The  sub-cutaneous  synovial  bursae  are  susceptible  of  inflam- 
mation, of  suppuration,  and  the  formation  of  large  abscesses, 
either  from  reiterated  pressure,  or  from  injections. 


ARTICLE  II. 
OF  THE  SYNOVIAL  MEMBRANES  OP  THE  TENDONS. 

§  204.  The  synovial  membranes  of  the  tendons,  membranse 
mucosse  teridinum,  are  serous  membranes,  moistened  with  an 
unctuous  fluid,  annexed  to  the  tendons  in  the  places  where 
they  rub  against  the  neighbouring  parts. 

They  have  received  the  improper  names  of  bursse,  bladders, 
capsules,  of  mucous,  mucilaginous,  synovial  sheaths,  &c.  They 
have  long  been  known:  Vesalius  and  A.  Spigel  mention  some 
of  them.  A  certain  number  have  been  accurately  described 
by  Albinus.  Jankius  was  the  first  who  gave  a  general  descrip- 
tion of  them;  he  was  acquainted  with  sixty  pairs.  Camper 
was  the  first  who  gave  a  figure  of  one  of  these  membranes. 
It  is  to  our  celebrated  Fourcroy,*  as  well  as  to  Munro,t  that 

*  Hist,  de  1'Acad.  R.  des  Sciences.    Palis,  1785,  1788. 
f  Jl  description,  etc.  with  tables. 


OF  THE  SYNOVIAL  MEMBRANES  OF  THE  TENDONS.        163 

this  part  of  anatomy  is  most  indebted.  Koch*  has  well  de- 
scribed these  membranes,  not  in  man  only,  but  in  several 
animals.  Gerlacht  was  the  first  who  described  and  figured, 
well,  those  that  are  found  in  the  neck  and  head,  llosenmul- 
lerj:  has  given  a  work  on  them,  augmented  by  that  of  Munro. 
Mascagni  has  given  a  good  figure  of  one  of  these  membranes 
in  his  Prodrome. 

§  205.  The  number  of  these  membranes  is  considerable,  but 
various;  at  this  day  we  know  about  one  hundred  pairs.  Like 
all  the  serous  membranes,  they  form  membranous  cavities 
without  openings;  but  with  reference  to  their  form,  they  are 
divided  into  two  kinds.  The  first  are  rounded  vesicles  hold- 
ing on  one  side  to  the  tendon,  and  on  the  other  to  the  part  on 
which  they  slide:  these  are  called  vesicular.  The  others  are 
vaginal,  surround  the  tendon  circularly,  and  another  part  line 
the  canala  in  which  it  is  contained,  these  two  isolated  parts 
joining  at  their  extremities  so  as  to  be  separated  by  a  space 
that  constitutes  the  cavity  of  the  membrane.  Among  these 
latter  there  are  some,  which  are  simple  at  one  end,  presenting 
digitations  at  the  other  which  answer  to  a  similar  number  of 
tendinous  parts  or  different  tendons,  these  latter,  at  first  united, 
afterwards  separate  from  each  other:  this  is  seen  in  the  wrist 
under  the  annular  ligaments. 

§  206.  The  cellular  tissue,  loose  and  membraniform,  which 
is  found  between  those  muscles  that  produce  the  great  and 
continued  movements,  as  under  the  latissimus  dorsi,the  rectus 
anticus  of  the  thigh,  the  muscles  of  the  calf,  &c.,  constitute, 
in  some  sort,  the  rudiments  of  the  membranes  in  question. 
Synovial  membranes  are  found  round  the  tendons  in  those 
places  where  the  latter  rub  against  the  bones,  slide  along  their 
surfaces,  or  on  other  parts,  or  where  they  are  reflected  and 
change  their  direction:  these  membranes  sometimes  exist  be- 
tween two  tendons  that  move  on  each  other.  The  glutaeus 

*  Ch.  M.  Koch.  De  bursts  tendin.  muc.  Lips.  1789. 

f  F.  E.  Gerlach.  De  bursts  tendinum  mucosis  in  capite  et  collo  reperiundis. 
cum  tabul.  centis.  Viteberg,  1793. 

$  Icones  et  descript.  bursar  mucosar.  curporis  hum.  Ed.  T.  Ch.  Rosenmul- 
Icr.  Lipsisc,  1799. 


164  GENERAL  ANATOMY. 

maximus,  at  the  spot  where  it  slides  on  the  trochanter,  the 
ohliquus  major  of  the  eye  at  the  place  where  it  is  reflected  in 
its  pulley,  the  lateral  peroneals  where  they  alter  their  course 
to  reach  the  sole  of  the  foot,  &c.  are  all  furnished  with  syno- 
vial  membranes.  Generally  these  membranes  are  connected 
with  bones  or  fibrous  rings.  They  are  very  common  about 
the  articulations,  because,  it  is  there  especially  that  the  tendons 
are  situated.  This  is  seen  in  the  wrist,  the  knee,  &c.  We 
there  find  the  two  kinds  of  which  we  have  spoken.  Some  of 
these  capsules  are  confounded  with  the  sub-cutaneous  or  arti- 
cular synovial  bursae :  that  of  the  triceps  for  instance,  is  not 
always  isolated,  and  frequently  appears  like  a  continuation  of 
the  synovial  capsule  of  the  knee. 

§  207.  The  adhering  face  of  these  membranes,  besides  be- 
ing attached  to  the  tendon  and  the  part  on  which  it  rubs,  is 
connected,  in  the  space  between  both  the  cellular  and  fatty 
tissues;  it  is  often  attached  to  fibrous  tissue,  as  for  instance,  to 
tendinous  or  fibro-cartilaginous  sheaths,  as  in  places  where 
the  tendons  slide  upon  bones,  and  in  which  place  the  peri- 
osteum is  like  cartilage.  Generally  their  interior  presents  a 
simple  cavity,  sometimes  a  compound  one,  traversed  by  par- 
titions, a  kind  of  fibrous  prolongations.  Fimbriated  prolonga- 
tions are  found  in  some,  in  that  situated  behind  the  calcaneum 
for  instance,  we  also  find  there  small  fatty  or  cellular  masses, 
but  in  those  only  that  are  formed  like  vesicles;  those  that  are 
vaginal  contain  none.  These  prolongations  have  been  assimi- 
lated to  excretory  ducts.  Rosenmuller  describes  follicles  in 
these  membranes — I  have  never  seen  any  there.  They  con- 
tain villosities  which  pour  out  synovia. 

§  208.  The  synovial  membranes  of  the  tendons  are  whitish, 
semi-transparent,  thin  and  soft,  those  that  are  vaginiform  par- 
ticularly, the  latter  having  also  external  ligamentous  sheaths. 
The  vesicular  bursar  are  thicker,  and  present  in  some  places  a 
fibrous  appearance.  The  texture  of  these  membranes  is  the 
same  as  that  of  the  others  of  the  same  genus;  their  tissue 
greatly  resembles  the  cellular  tissue.  The  fibres,  the  fringes 
and  adipose  masses,  common  to  all  the  serous  system,  are  also 
found  here.  Serous  vessels  which  become  visible  in  inflam- 


OF  THE  SYNOVIAL  MEMBRANES  OF  THE  TENDONS.         1G5 

mation  and  some  blood  vessels  particularly  apparent  in  the 
fringes,  enter  into  the  composition  of  these  membranes  whose 
lymphatics  and  nerves  are  entirely  unknown.  The  liquid 
they  contain  is  viscid,  more  abundant  than  in  the  sub-cutane- 
ous mucous  bursae,  yellowish  and  sometimes  reddish;  it  is 
oleiform,  partly  coagulable,  and  contains  albumen  and  mu- 
cus: it  is  more  viscid  in  the  mucous  bursas  which  are  the  most 
extensive.  Mr.  Koch  has  found  some  difference  to  exist  in 
this  liquid,  as  examined  in  different  animals,  as  in  the  ox,  the 
horse  and  the  hog. 

§209.  The  properties  of  the  tendinous  capsules  have  nothing 
particular.  Their  functions  are  to  secrete  and  contain  a  mu- 
cilaginous liquid,  which  facilitate  the  sliding  by  diminishing 
the  loss  of  motion  which  results  from  friction. 

But  little  is  known  respecting  the  development  of  these 
membranes.  According  to  some,  they  are  greatest  in  number 
in  young  subjects,  and  by  increasing  in  size  and  meeting  each 
other,  they  become  partly  confounded  in  old  age.  M.  Seiler, 
on  the  contrary,  asserts  that  they  diminish  in  extent  in  old 
persons,  and  partly  disappear. 

§  210.  They  undergo  some  changes.*  Dropsy  is  an  affec- 
tion not  very  rare  in  them,  those  which  are  in  the  neighbour- 
hood of  the  skin  are  particularly  liable  to  it;  this  may  occasion 
the  disease  to  be  confounded  with  hygroma.  The  name  of 
ganglion  is  given  to  the  little  circumscribed  tumours  resulting 
from  it,  and  which  are  often  cysts  also.  These  tumours  are 
particularly  met  with  in  the  hamstrings,  wrist,  foot,  &c.;  they 
contain  a  serous,  albuminous,  yellowish  or  reddish  liquid, 
similar  in  colour  and  consistence  to1  currant  jelly.  The  ab- 
sorption of  this  liquid  is  effected  very  slowly:  it  is  accelerated 
by  crushing  the  tumours  that  contain  it,  as  this  disperses  it  in 
the  cellular  tissue.  These  tumours  are  occasionally  found  much 
larger;  voluminous  collections  of  purulent  serum  that  have 
been  observed  under  the  great  muscles  of  the  backj  under  the 
deltoid,  &c.  and  which  have  been  confounded  with  the  com- 

*  Monro,  op.  cit.  Koch.  De  morbis  bursarum  tcndinum  mucosaram* 
Lips.  1790. 


166  GENEKAL  ANATOMY. 

mon  abscess  of  the  cellular  tissue,  are  seated  in  membranes  of 
this  kind  or  in  those  analogous  to  them. 

Inflammation  of  the  membranes  of  which  we  are  treating  is 
a  serious  matter;  it  may  be  observed  in  one  of  the  varieties  of 
paronychia.  The  results  are  adhesions  or  an  abscess  which 
opens  externally,  and  in  either  case  the  power  of  motion  is 
destroyed.  When  the  adhesion  is  filamentous  it  is  sometimes 
finally  removed.  Chronic  inflammation  produces  nearly  simi- 
lar results:  it  may  also  induce  suppuration. 

Solid  cartilaginous  bodies  have  been  found  in  the  interior 
of  these  membranes  by  Munro,  and  since  by  many  others. 
We  frequently  find  in  them,  a  great  number  of  small  bodies 
resembling  apple  or  pear  seeds  in  size  and  shape,  that  have 
been  considered  as  animated  and  for  which  the  name  of  ace- 
phalo  cystis  planet,  has  been  proposed.  They  have  been 
most  often  found  under  the  anterior  ligament  of  the  carpus, 
and  sometimes  also  in  other  membranes  of  the  tendons,  as  in 
those  of  the  great  gluteus,  of  the  long  flexor  of  the  thumb,  &c. 
An  incision  gives  them  issue,  but  the  general  result  is  a  very 
serious  inflammation  and  at  all  events  an  intimate  adhesion, 
which,  in  the  wrist,  for  instance,  confounds  all  the  flexors  in 
one  single  bundle,  and  renders  the  fingers  motionless.  The 
inflammation  of  the  synovial  tendinous  membranes  generally, 
merits  the  attention  of  pathologists.  It  is  the  same  with  the 
greater  part  of  their  morbid  changes,  which  have  often,  under 
the  name  of  white  swellings,  been  confounded  with  diseases 
of  the  articulations,  in  whose  vicinity  they  are  situated. 


ARTICLE  III. 
OP  THE  ARTICULAR  SYNOVIAL  CAPSULES. 

§  211.  Under  this  name,  capsulx  synovialeswc  designated, 
Ihe  serous  membranes  of  the  diathrodial  articulations.  Most 
of  them  belong  to  the  bones,  some  to  cartilages,  as  is  the  case 
with  the  larynx.  These  membranes,  like  the  preceding  ones, 


OF  THE  ARTICULAR  SYNOVIAL  CAPSULE.  1G/ 

are  humected  by  a  liquid  internally,  and  impart  a  similar  facility 
of  sliding  to  the  parts  they  invest. 

For  a  long  time  they  were  confounded  with  the  capsular 
ligaments  of  the  joints.  Nesbit,  Bono,  and  W.  Hunter  had  al- 
ready observed  that  they  formed  a  membrane  distinct  from 
the  articular  ligaments  and  cartilages.  Monro  had  remarked 
their  analogy  to  the  other  synovial  and  serous  membranes; 
Bichat  has  fixed  our  attention  more  particularly  upon  these 
membranes,  and  has  given  a  more  complete  general  descrip- 
tion of  them.  Monro  and  Mascagni  have  figured  them. 

§  212.  The  number  of  these  membranes  is  very  great,  being 
about  equal  to  that  of  the  articulations.  This  number  is  not 
quite  equal  to  that  of  the  latter,  because,  on  the  one  hand,  some 
of  these  membranes  are  common  to  several  articulations,  as  in 
the  carpus,  for  instance,  and  on  the  other,  some  of  the  articu- 
lations contain  several  membranes.  They  are  found,  how- 
ever, in  the  articulations  only. 

§213.  The  following  varieties  are  observed  in  the  configura- 
tion of  these  membranes:  1st,  some  resemble  simple,  rounded 
sacs,  like  the  vesicular  membranes  of  the  tendons:  this  is  seen 
in  the  articulations  of  the  phalanges  with  each  other  and  with 
the  metatarsus  and  metacarpus:  here  is  nothing  at  all  complex, 
and  a  small  round  ampulla  is  all  that  is  attained  by  insuffla- 
tion. 2d,  in  some  articulations,  the  cavity  of  the  membrane 
seems  to  be  traversed  by  a  ligament  or  tendon  about  which 
this  is  reflected,  forming  for  it  a  sheath,  continuous  at  its  two 
extremities  with  the  common  envelope,  that  the  synovial 
membrane  furnishes  to  the  articulations;  this  synovial  mem- 
brane is  then  vaginiform:  this  disposition  is  found  in  thecoxo- 
femoral,  scapulo-humeral  articulations,  &c.  3d,  a  greater  de- 
gree of  complication  is  observed  in  some  other  articulations;  in 
that  of  the  knee,  for  instance,  we  perceive  a  common  enve- 
lope, sheaths  for  the  tendon  of  the  popliteal  muscle  and  the 
adipose  ligament,  and  folds  moreover  invest  the  semi-lunar 
and  crucial  ligaments,  which  raise  up  the  membrane  and  project 
into  the  articulation.  We  might  then  establish,  nearly  the  fol- 
lowing order  in  the  complication  of  the  synovial  membranes: 

simple  ampulla;  an  ampulla  raised  up  by  fatty  flakes;  this  last 
23 


16S  GENERAL  ANATOMY. 

disposition  joined  to  the  presence  of  sheaths;  lastly,  besides  this 
latter,  folds  formed  by  parts  which  extend  into  the  articulation, 
and  that  are  covered  by  the  membrane.  All  these  forms,  which 
are  so  various,  are  to  be  referred  finally  to  the  vesicular  form. 
§214.  The  external  surface  of  the  synovial  membranes  is 
more  or  less  intimately  connected  with  the  neighbouring 
parts.  They  all  adhere  closely  to  the  articulating  surfaces  of 
the  bones,  or  rather  to  the  cartilages  which  invest  them,  by 
the  two  extremities  of  the  kind  of  sac  they  represent.  Their 
connexion  with  these  cartilages  is  so  close  as  to  occasion  a 
belief  that  the  latter  is  naked:  Nesbit,  Bonn  and  W.  Hunter, 
however,  long  ago  announced  the  existence  of  a  prolongation 
of  the  synovial  membranes,  upon  the  articulating  surfaces  of 
the  bones.  It  is  to  Bichat  in  particular,  that  we  are  indebted 
for  having,  incontestably,  established  this  truth.  Some  au- 
thors, however,  such  as  Gordon  and  M.  Magendie,  still  raise 
doubts  on  the  subject.  Many  facts  demonstrate  the  presence 
of  the  synovial  membranes  on  the  cartilages.  When  these 
membranes  are  inflamed,  their  redness,  which  in  time  becomes 
apparent,  extend  around  the  circumference  of  the  cartilage, 
and  becomes  less  and  less  sensible  as  it  advances  towards  its 
centre,  the  membrane  becoming  more  and  more  identified 
with  the  cartilage;  the  centre  itself  is  finally  penetrated  with 
vessels,  but  the  cartilage  is  coloured  only  at  its  surface,  pre- 
serving in  its  thickness  the  whiteness  peculiar  to  it.  The 
bridles  which  are  sometimes  formed  in  the  synovial  mem- 
branes arise,  indifferently,  from  all  parts  of  their  extent,  and 
it  is  observed  that  when  they  adhere  to  the  cartilage,  their 
bases  are  less  closely  united  to  it,  and  that  in  this  place,  the 
membrane  becomes  apparent  as  it  naturally  is  about  the  arti- 
culating surfaces:  in  this  manner,  the  synovial  membrane 
becomes  apparent  even  on  the  centre  of  the  cartilage.  The 
fungous  degeneration  peculiar  to  the  synovial  membrane  is 
also  to  be  found  on  the  cartilage.  Finally  direct  inspection 
demonstrates  the  continuity  of  this  membrane.  By  obliquely 
raising  a  slice  of  cartilage,  and  afterwards  bending  it  back  so 
as  to  break  it  at  its  base,  it  still  holds  by  the  synovial  mem- 
brane which  covers  it  equally  with  the  rest  of  the  cartilage. 


OF  THE  ARTICULAR  SYNOVIAL  CAPSULE.  169 

When  a  bone  is  sawed,  break  the  cartilage  at  its  extremity, 
and  the  connexion  is  still  kept  up  between  the  two  halves  by 
the  synovial  membrane  which  extends  from  the  one  to  the 
other. 

Throughout  the  remainder  of  their  extent,  i.  e.  on  the  edge 
of  the  articulation,  the  synovial  membranes  are  attached  to  the 
articulary  ligaments,  in  an  equally  close  way  as  is  seen  in  the 
scapulo-humeral  articulation  :  the  adhesion  is  particularly  in- 
timate in  the  middle  and  becomes  looser  towards  the  extremi- 
ties. In  the  intervals  between  the  ligaments,  these  membranes 
correspond  to  the  fatty  and  cellular  tissues:  these  tissues  form 
distinct  pellets  there  as  well  as  near  the  place  where  the  sy- 
novial membrane  leaves  the  ligaments  to  be  reflected  on  the 
bones. 

The  internal  surface  is  smooth,  polished,  contiguous  to 
itself,  lubricated  by  the  synovia,  and  furnished  with  villosities 
and  fimbriated  prolongations. 

§  215.  The  synovial  membranes  are  thin,  soft,  semi-trans- 
parent, whitish,  extensible  to  a  certain  degree,  although  less 
so  than  the  splanchnic  serous  membrane,  and  retractile,  a  fact 
demonstrated  by  their  dropsy  and  their  return  to  their  original 
dimensions  after  the  evacuation  of  the  accumulated  fluid.  Their 
rupture  in  relaxations  depends  less  on  their  want  of  extensi- 
bility, than  on  their  close  connections  and  the  small  extent  of 
their  folds. 

§  216.  These  membranes  are  provided  with  fatty  pellets 
placed  on  their  exterior  or  even  in  their  interior,  and  impro- 
perly called  the  synovial  glands  of  Havers.  These  pellets, 
perceived  by  Vesalius  and  Etienne,  described  by  Cowper  and 
particularly  by  Cl.  Havers,*  until  the  time  of  Monro,  were 
regarded  as  the  secreting  organs  of  the  synovia,  t  Their  size 
varies  according  to  the  quantity  of  fat  they  contain  :  they  al- 
ways contain  more  or  less  of  this  fluid,  and  are  almost  entire- 
ly formed  of  adipose  tissue.  The  fringes  exist  on  the  inte- 

*  De  ossibus,  sernio  iv.  chap.  I. 

f  See  Pitschel.  De  axungid  articular.  Lips.  1740. — Hanse.  De  unguine 
articulari,  efusque  vitiis.  Lips.  1774. 


170  GENERAL  ANATOMY. 

rior  of  the  membrane,  at  the  spots  where  the  pellets  are  placed 
without.  The  points  in  which  these  different  objects  are 
found,  are  those  where  the  membrane  is  most  vascular.  The 
fringes  contain  in  their  thickness,  cellular  tissue,  fat  and  blood 
vessels:  the  other  parts  of  the  synovial  membranes  only  re- 
ceive serous  vessels.  Lymphatics  are  apparent  in  some  of 
these  membranes  only;  it  is  useless  again  to  revert  to  the 
theory  of  Mascagni  which  this  author  applies  to  all  the  trans- 
parent membranes.  The  nerves  of  the  synovial  capsules  are 
not  known. 

§217.  The  liquid  secreted  by  these  membranes  or  the  sy- 
novia, synovia,  so  named  by  Paracelsus  on  account  of  its  im- 
perfect resemblance  to  the  white  of  egg,  is  the  result  of  a  per- 
spiratory secretion,  although  various  other  opinions  have  been 
entertained  about  the  mechanism  of  its  formation.  This  fluid 
is  not,  as  it  was  for  a  long  time  thought  to  be,  the  product  of 
a  mixture  of  serum  and  fat;  the  marrow  of  the  bones  does 
not  transude  to  form  it  as  we  have  seen;  the  synovia,  in  its 
natural  state  does  not  even  contain  any  oil.  The  supposed 
glands  of  Havers  can  not,  from  what  we  have  said,  fulfil  the 
functions  ascribed  to  them,  and  the  fringes  that  surmount 
them,  are  not,  as  he  thought,  excretory  ducts:  it  is  but  very 
lately,  however,  that  this  glandular  structure  has  been  sup- 
posed to  have  been  found;  in  fact,  nothing  glandular  can  be 
observed  in  the  synovial  masses,  no  granulations  nor  excre- 
tory ducts.*  Even  the  fat  they  contain  is  not  essential  to 
their  structure,  and  besides,  as  there  is  no  oil  in  the  synovia, 
it  is  not  from  the  transudation  of  the  first  of  these  fluids,  when 
it  exists,  that  the  second  owes  its  origin.  Rosenmuller  pre- 
tends that  there  are  secretory  follicles  in  these  adipose  pellets: 
I  have  never  seen  these  follicles,  nor  do  I  know  that  any  one 
since  has  proved  their  existence.  The  secretion  of  the  syno- 
via then,  is  neither  glandular,  follicular,  nor  a  simple  result  of 
transudation,  but  truly  perspiratory;  it  has  its  seat  throughout 
the  whole  extent  of  the  synovial  membranes,  that  portion  of 
them,  particularly,  which  surmounts  the  fringes,  and  which 

*  See  Hey  liters,  Dissertatio  physiol.  ana/,  de  fabrica  arlicul,  1803. 


OF  THE  ARTICULAR  SYNOVIAL  CAPSULE.  171 

is  owing  to  the  great  number  of  vessels  it  contains.  The  sy- 
novia is  partly  taken  up  by  absorption,  and  its  quantity  in  a 
normal  state,  being  always  about  the  same,  supposes  an  equi- 
librium between  absorption  and  secretion. 

This  liquid  known  to  the  Greeks  who  called  it  JU|Q  tw>  apflpw, 
and  long  known  as  axunguia,  is  viscid  and  has  a  saltish  taste; 
its  specific  gravity  is  105,  that  of  water  being  100.  Its  che- 
mical composition  has  been  examined  in  animals  as  well  as 
man,  but  more  particularly  in  the  ox  by  Margueron,  Four- 
croy,  T.  Davy,  Hildebrandt,  M.  Orfila  and  several  others. 
There  are  found  in  it  water,  albumen,  mucus  or  incoagulable 
matter,  considered  by  some  as  mucilaginous  gelatine,  a  thready 
matter,  which  some  think  is  fibrine  and  others  albumen  in  a 
particular  state,  soda,  muriate  of  soda,  phosphate  of  lime,  and 
an  animal  matter  said  to  be  uric  acid.  The  use  of  the  synovia 
is  to  diminish  friction  and  to  facilitate  thereby  the  sliding  of 
the  parts. 

§218.  The  synovial  capsules  of  the  articulations  present 
some  pathological  alterations.*  They  are  repaired  when  di- 
vided; but  their  mode  of  reunion  is  not  well  understood; 
there  are  no  precise  facts  in  the  history  of  wounds  of  the  arti- 
culations, and  of  luxations,  relative  to  it.  New  synovial  mem- 
branes are  sometimes  formed  as  is  observed  in  false  joints,  after 
unreduced  luxations;  in  this  case,  described  by  Dr.  Thompson 
and  observed  by  myself,  the  remains  of  the  old  capsule  and 
the  cellular  tissue  united,  form  a  new  membrane  very  similar 
to  the  first.  In  false  articulations,  which  succeed  to  fractures 
that  have  not  been  consolidated,  there  is  also  found  a  closed 
membrane,  smooth  within,  containing  a  viscid  liquid  more  or 
less  analogous  to  the  synovia. 

Dropsy  of  the  joints  constitutes  hydrarthrosis;  in  this  affec- 
tion, the  synovia  undergoes  various  changes. 

§219.  Inflammation  produces  the  same  alterations  of  tissue 
and  functions  in  these,  as  in  the  serous  membranes  generally. 

*  See  Reimarus,  de  tumore  ligament,  etc.  Leyd.  1557. — Wynpersse,  de 
ancylosi.  Leyd.  1783. — Ejusd.de  ancylpathol  Leyd.  1783. — Brodie,  Traite 
des  maladies  des  articulations.  Paris,  1819. 


172  GENERAL  ANATOMY. 

They  become  a  little  thickened,  redden  to  a  greater  or  less  ex- 
tent, are  covered  with  albuminous  granules,  and  sometimes 
finally  form  adhesions.  The  inflammation  may  terminate  by 
resolution,  and  it  then  leaves  a  stiffness,  occasioned  by  the 
thickening  of  the  surrounding  parts  :  the  membrane  itself, 
also,  generally  remains  thickened.  Flowing  of  pure  synovia, 
lactescent  serum,  or  serum  containing  albuminous  floculi,  or 
even  true  pus,  may  also  result  from  the  inflammation.  The 
adhesions  it  finally  forms,  constitute  one  of  the  species  of  an- 
chylosis. There  are,  as  is  well  known,  several  kinds  of  this 
disease:  they  all  depend,  however,  upon  the  changes  of  the 
synovial  membrane,  and  sometimes  of  the  parts  exterior  to  it. 
Thus  in  false  anchylosis,  there  appears  to  be  a  thickening,  an 
induration  of  all  the  parts  surrounding  the  articulations.  Ano- 
ther species,  to  which,  if  worthy  of  preserving,  the  epithet 
false,  might  be  applied,  is  characterized  by  adhesions  of  the 
synovial  membrane.  The  articulation  then  becomes  an  am- 
phiarthrosis,  bridles  or  synovial  lamina  uniting  the  diarthro- 
dial  surfaces:  these  bridles  are  so  numerous  that  they  repre- 
sent a  sort  of  cellulosity;  according  to  their  number,  length 
and  extensibility,  the  motions  are  more  or  less  limited;  a 
thickening  and  induration  of  the  soft  parts,  are  added  to  this, 
the  end  of  all  which  is,  that  the  parts  never  perfectly  resume 
their  accustomed  motion.  In  true  anchylosis,  adhesions  are 
not  only  established  between  the  articulating  surfaces,  but  these 
surfaces  become  soldered  together,  confounded,  the  continuity 
is  perfect  between  the  bones,  whose  compact  laminae,  as  well 
as  whose  cartilaginous  laminae  which  separate  them,  finally  dis- 
appear, so  that  their  spongy  tissue  is  confounded;  this  change 
begins  in  the  synovial  membrane,  for  this  reason  we  speak  of 
it  here.  Ulceration  is  a  more  rare  termination  of  inflamma- 
tion in  the  synovial  membranes. 

§  220.  In  white  swellings,  among  which  are  included  various 
changes,  such  as  inflammation,  dropsy,  diseases  of  the  carti- 
lages, &c.,  is  found  an  alteration  peculiar  to  the  synovial  mem- 
branes: it  is  a  state  in  which  these  membranes  are  converted 
into  a  fungous  substance,  from  whence  springs  a  vegetation 
that  extends  to  the  skin,  and  even  penetrate  through  it.  Reima- 


OF  THE  SEROUS  SPLANCHNIC  MEMBRANES.  173 

rus,  Brambilla,  and  M.  Brodie  have  described  these  cancerous 
fungi. 

§  221,  Foreign  bodies  are  formed  in  the  articulations:  they 
are  most  generally  seated  in  the  knee.  Their  size  as  well  as 
their  number  and  consistence  varies,  as  has  been  already  stated, 
while  speaking  of  the  serous  system  in  general;  they  are  form- 
ed outside  the  synovial  membrane,  and  appear  to  be  the  result 
of  a  peculiar  change  of  the  nutrition.  They  gradually  advance 
into  the  interior  of  the  membrane,  and  are  finally  detached  in 
the  way  before  mentioned.  Their  presence,  which  is  accom- 
panied by  violent  pain,  when  placed  between  the  articulating 
surfaces,  produces  no  uneasiness,  when  in  moveable  parts,  and 
where  the  articulation  is  loose.  Depressions  more  or  less  deep, 
are  sometimes  finally  made  by  their  pressure  on  the  cartilages, 
and  as  these  depressions  correspond  in  form  to  that  of  the  bo- 
dies lodged  there,  it  has  been  said,  that  the  latter  were  pieces 
of  cartilage  separated  by  external  violence;  but  to  prevent  the 
admission  of  this  opinion,  it  is  sufficient  to  consider,  that  in 
the  greater  number  of  cases  in  which  those  bodies  are  found, 
the  depressions  do  not  exist,  that  they  have  no  resemblance  to 
fractured  surfaces,  and  that  the  bodies  are  much  thicker  than 
the  articular  cartilages  themselves. 


ARTICLE  IV. 

OF  THE  SEROUS   SPLANCHNIC  MEMBRANES. 

§  222.  The  serous  membranes,  properly  so  called,  also  styled 
the  diaphanous  membranes,  are  those  which  line  the  splanchnic 
cavities,  and  which  furnish  tunicks  more  or  less  perfect,  to  the 
viscera  situated  therein. 

§223.  These,  like  all  other  serous  membranes,  were  for  a 
long  time  confounded,  both  in  their  healthy  and  diseased  con- 
ditions, with  the  organs  they  envelop,  and  the  parts  they  in- 
vest. With  respect  to  the  first,  however,  each  of  these  mem- 
branes had  been  successively  and  exactly  described,  independ- 
ently of  the  parts  they  cover;  some  anatomists,  Monro  for  in- 


174  GENERAL  ANATOMY. 

stance,  had  even  indicated  the  analogy  that  exists  between 
them.  As  regards  their  pathology,  Sauvages  and  M.  Pinel 
had  already  established  an  order  of  inflammation  for  that  of  the 
diaphanous  membranes,  but  one  comprehending  the  inflamma- 
tions of  the  stomach,  of  the  intestine,  bladder,  and  epiploon,  as 
so  many  genera.  Various  pathologico-anatomical  observations, 
those  of  T.  G.  Walter  on  the  peritoneum,  in  particular,  had 
shown  that  this  membrane,  like  all  other  serous  membranes, 
could  be  affected  throughout  its  whole  extent,  and  independ- 
ently of  the  subjacent  parts;  finally,  Dr.  Carmichael  Smith  had 
noted  with  exactness,  the  identity  of  the  inflammation  of  all 
the  diaphanous  membranes,  when  Bichat  gave  his  exact  and 
complete  description  of  the  serous  membranes,  and  particu- 
larly of  the  arachnoid.  Descriptions  of  some  of  these  mem- 
branes have  been  given  since;*  but  little,  however,  has  been 
added  to  what  our  celebrated  anatomist  has  said;  more  has 
been  added  to  ther  pathological  history. 

§  224.  The  serous  membranes  of  which  we  are  now  speak- 
ing, are  situated  in  the  cavities  of  the  trunk,  which  they  line; 
they  there  invest  the  most  important  organs,  those  that  are  the 
most  essential  to  life.  These  membranes  are  distinct  and  se- 
parate from  each  other;  their  number  is  but  small;  viz.  1st, 
the  peritoneum  in  the  abdomen,  where  it  invests  more  or  less 
perfectly  the  greater  part  of  the  organs  of  digestion,  that  are 
contained  in  this  cavity,  and  rather  less  the  genital  and  urinary 
organs;  2d  and  3d,  the  two  pleuras,  and  4th,  the  pericardium 
in  the  chest,  where  each  one  of  these  membranes  is  restrained 
to  a  single  organ,  and  to  the  parietes  of  its  cavity;  5th,  the 
arachnoid  in  the  cranium,  and  in  the  spinal  canal;  6th  and  7th, 
in  man  only,  the  tunica  vaginalis. 

The  extent  of  these  membranes,  collectively,  is  very  consi- 
derable, and  greatly  surpasses  that  of  the  skin.  The  perito- 
neum is  the  greatest  of  these  membranes,  its  extent  being 
equal,  at  least,  to  that  of  all  the  others  together. 

§  225.  The  general  description  of  the  serous  membranes, 

*  See  JLangenbeck.   Commentarium,  de  structure,  peritonceci.  ect.  cum  tabu- 
Its.  Getting,  1817. — L.  Rolando.   Osservazioni  sul peritonea  et  sulla  pleura 
in  mem.  della  real  dead,  de/le  srienze.  Tom.  xxiv,  Turin,  1820, 


OP  THE  SEROUS  SPLANCHNIC   MEMBRANES.  175 

has  already  in  a  great  measure  explained  the  species  of  which 
we  are  now  speaking,  and  which  may  be  considered  as  the 
type  of  the  genus.  Their  form  is  the  same  as  that  of  all  the 
serous  membranes,  that  of  a  bladder  without  an  opening,  and 
with  contiguous  parietes.  On  the  one  hand,  it  lines  the  inter- 
nal surface  of  the  parietes  of  the  cavity  in  which  they  are  con- 
tained, and  on  the  other,  it  furnishes  tunicks  or  external  en- 
velopes to  the  organs.  The  pleura,  the  pericardium,  and  tu- 
nica vaginalis  have  a  tolerably  simple  conformation,  their  pa- 
rietal and  visceral  portions,  continuing  around  the  point  where 
the  organ  they  invest  is  attached  by  vascular  prolongations, 
to  the  parietes  of  the  cavity  that  contains  it.  As  to  the  arach- 
noid and  peritoneum,  their  disposition  is  a  little  more  com- 
plex, without,  however,  ceasing  to  be  essentially  the  same. 
With  respect  to  the  first,  the  complication  is  owing  to  the 
great  number  of  vessels  and  nerves  that  terminate  in,  or  de- 
part from  the  brain.  Now  on  each  of  these  parts,  the  arach- 
noid forms  a  sheath,  which  continues  to  one  of  its  extremities 
with  the  visceral  lamina  of  the  membrane,  and  to  the  other, 
with  its  parietal  lamina,  an  arrangement,  previously  pointed  out 
and  figured  by  Bonn,  to  which  Bichat  has  particularly  drawn 
our  attention,  and  from  which  it  results,  on  the  one  hand,  that 
the  membranous  cavity  is  not  open,  and  that  the  parts  of  the 
membranes  are  continuous  to  one  another.  As  to  the  perito- 
neum, its  complexity  depends  upon  the  great  number  of  parts 
to  which  it  furnishes  coverings,  and  upon  the  various  disposi- 
tion of  these  parts,  of  which  some  are  very  near  the  posterior 
wall  of  the  abdomen,  whence  they  receive  their  vessels,  and 
are  simply  covered  with  the  peritoneum;  others  again  are  re- 
moved from  it,  sometimes  greatly  so,  and  are  suspended  to 
membranous  bridles  which  contain  the  vessels  in  their  thick- 
ness. Its  complexity  depends  also  upon  vascular  prolonga- 
tions, projecting  beyond  the  viscera,  and  to  which  the  serous 
membrane  furnishes  epiploical  or  floating  envelopes.  This 
membrane  is  peculiar  also  in  being  the  only  one  that  has  an 
opening  communicating  externally  through  the  fimbriated  bo- 
dy, and  fallopian  tubes.  More  extensive  details  on  the  con- 
formation of  the  splanchnic  serous  membranes,  belong  to  the 
24 


176  i-ENEKAL  ANATOMY. 

special  anatomy  of  these  membranes,  and  particularly  to  that 
of  the  peritoneum  and  arachnoid. 

§  226.  Of  the  two  surfaces  of  these  membranes,  one  is  gene- 
rally free,  in  a  healthy  state,  and  the  other  adherent.  The 
free  surface  is  shining,  moist,  and  appears  polished ;  it  is,  how- 
ever, covered  with  small  villosities  which  become  visible  on 
looking  at  it  under  water,  and  which  the  inflammatory  irrita- 
tion renders  very  apparent.  It  is  to  the  serous  membranes 
which  envelop  and  line  them,  that  the  organs  and  parietes  of 
the  splanchnic  cavities  owe  their  shining  aspect;  wherever 
they  are  without  it,  they  have  not  the  same  appearance.  This 
free  surface,  every  where  contiguous  to  itself,  as  well  as  the 
serosity.that  humects  it,  creates  a  distinctness,  a  true  isolation 
between  parts  very  nearly  approximated;  they  also  singular- 
ly facilitate  the  motions  of  these  parts. 

§  227.  The  other  surface  of  the  serous  membranes  is  almost 
universally  adherent,  either  to  the  viscera  or  the  walls  of  the 
cavities;  there  are  only  some  prints  of  the  visceral  lamina  of 
the  arachnoid,  which  are  free  on  the  two  surfaces,  every  where 
else  the  external  surface  of  the  serous  membranes  is  adherent. 
This  adhesion  is  on  one  side  with  the  parietes  of  the  cavities, 
and  on  the  other,  with  the  surface  of  the  viscera.  The  degree 
or  solidity  of  this  adhesion  generally  varies.  In  general, 
wherever  the  serous  membranes  are  connected  with  a  liga- 
mentous  tissue,  as  with  the  dura  mater,  the  pericardium,  the 
aponeuroses  of  the  abdominal  parietes,  the  tunica  albuginea  of 
the  testis,  &c.  there  this  adhesion  is  very  intimate;  it  is  also 
very  great  with  the  muscular  and  other  parts,  as  the  heart, 
lungs,  stomach,  intestines,  &c. ;  it  is  much  less  so,  in  other 
places,  as  where  the  membrane  passes  from  an  organ  to  the 
walls  of  a  cavity,  and  vice  versa;  where  it  forms  bridles,  or 
floating  prolongations  that  contain  vessels;  in  the  places  where 
the  sub-serous  cellular  tissue  contains  fat,and,  generally,  where- 
ever  it  is  loose. 

§  228.  These  differences  are  of  sufficient  importance  to  de- 
mand further  attention;  the  consequence  is,  that  when,  for 
Example,  the  uterus,  the  bladder,  the  stomach  and  the  intes- 
tines augment  in  volume,  the  peritoneal  bridles  and  ambiant 


OF  THE  SEBOUS  SPLANCHNIC   MEMBRANES.  177 

folds  open,  spread  out,  and  are  applied  to  the  organs,  and  then 
when  the  latter  recede  to  their  original  condition,  the  mem- 
brane becomes  foreign  to  them;  this  is  owing  to  the  laxity  of 
the  sub-serous  cellular  tissue,  near  the  adhering  edge  of  these 
folds.  When  a  hernia  is  produced  in  the  groin  and  increases 
in  size,  it  is  chiefly  by  the  displacement,  the  sliding  of  the 
serous  membrane,  assisted  by  the  laxity  of  the  adhesions,  that 
the  sac  increases;  when,  on  the  contrary,  an  umbilical  hernia 
augments  in  volume,  it  is  by  thinning  and  distention,  that  the 
sac  increases,  the  adhesion  of  the  peritoneum  about  the  umbi- 
licus being  intimate.  Bichat  has,  perhaps,  exaggerated  a  little 
the  influence  which  the  laxity  of  the  adhesions  of  the  serous 
membranes,  may  have  in  limiting  their  diseases  and  those  of 
the  subjacent  parts. 

§  229.  The  physical  properties  of  these  membranes  are. 
those  of  the  serous  system  in  general  already  described:  they 
are  thin,  but  this  tenuity  is  not  the  same  in  all,  neither  is  it  so 
in  all  parts  of  the  same  membrane,  nor  in  different  individuals. 
Soft,  semi-transparent,  &c.;  their  extensibility  is  strongly 
marked,  more  so  than  that  of  the  synovial  membranes;  their 
strength  tolerably  great,  and  much  greater  than  that  of  the 
cellular  tissue;  they  are  slightly  elastic.  When  these  mem- 
branes are  distended  beyond  a  certain  degree,  their  texture 
becomes  loose;  this  looseness  is  on  the  free  surface;  the  rest 
of  the  thickness  of  the  membranes,  resists  the  laceration  more 
strongly,  or  yields  more  to  the  distention. 

§230.  They  all  consist  of  one  lamina,  which  is  so  much 
the  more  dense  and  close,  if  examined  on  the  free  surface,  and 
whose  texture  is  more  lax  on  the  opposite  side  where  it  be- 
comes flaky  and  is  confounded  with  the  common  cellular  tissue. 
Until  the  period  when  Douglass  gave  an  exact  description  of 
the  peritoneum,  this  membrane  as  well  as  those  of  the  same 
species  was  considered  as  bifoliate,  and  containing  the  viscera 
in  the  space  between  their  separated  layers:  it  was  an  error 
which  he  refuted,  and  that  Vacca  and  others  have  vainly  tried 
to  revive.  The  pretended  external  leaflet  is  nothing  more 
than  the  sub-serous  cellular  tissue,  so  well  described  by  Doug- 
lass. They  consist  essentially  of  one  layer  of  extremely  close 


178  GENERAL  ANATOMY. 

and  condensed  cellular  tissue,  more  and  more  distinct  from 
the  cellular  tissue,  from  the  adhering  surface  where  it  insensi- 
hly  continues  with  it,  to  the  free  surface  where  it  greatly  dif- 
fers; fibres  or  little  interlaced  fasciculi  are  not  so  manifest  in 
it  as  in  the  synovial  membranes.  The  floating  appendages  of 
these  membranes  contain,  also,  free  cellular  tissue,  and  often 
fatty  tissue ;  they  are  much  more  vascular  than  the  other  serous 
or  synovial  membranes.  They  contain  an  immense  quantity 
of  white  or  serous  vessels  which  become  visible  by  injection, 
congestion,  or  inflammation  and  some  very  delicate  red  ves- 
sels, which  belong  to  their  external  surface,  and  particularly 
to  the  sub-serous  cellular  tissue,  as  may  be  proved  by  detach- 
ing the  membrane,  which  is  found  to  be  white  in  those  places, 
where  one  would  have  supposed  there  was  a  number  of  red 
vessels  that  were  in  fact  only  seen  through  it.  The  red  ves- 
sels are  particularly  abundant  in  the  loose  or  floating  folds. 
Nerves  have  been  traced  to  these  membranes,  but  not  into 
their  substance. 

§  231.  These  membranes,  when  dried,  become  transparent, 
elastic  and  tolerably  firm,  assuming  a  light  yellowish  colour; 
by  immersion  in  water  they  resume  their  original  properties. 
Maceration  first  renders  them  soft,  opaque  and  thick,  then 
pulpy,  and  ends,  but  after  a  very  long  time,  by  dissolving 
them.  In  bodies  beginning  to  be  decomposed,  these  mem- 
branes impregnate  themselves  with  liquids  on  the  one  hand, 
and  permit  them  to  transude  on  the  other,  hence  their  diver- 
sity of  colour.  Fire  and  boiling  water  render  them  horny. 
Continued  ebullition  converts  them  into  gelatine  and  a  little 
albumen.  These  different  characters  approximate  them  to 
the  cellular  and  ligamentary  tissues. 

The  force  of  formation  is  less  developed  in  them,  than  in 
the  free  cellular  tissue.  Irritation  produces  no  sensible  motions 
in  them,  but  it  changes  their  secretion  and  texture;  it  inflames 
them.  They  are  sensible  in  this  state  only,  in  which  they 
usually  become  the  seat  of  violent  pain. 

§232.  In  a  state  of  life  and  health  they  are  humected  on 
their  contiguous  surface  by  serum  they  are  continually  depo- 
siting and  absorbing.  This  secretion  had  been  attributed  to 


OF  THE  SEROUS  SPLANCHNIC  MEMBRANES.  179 

certain  glands  supposed  to  be  lodged  in  their  tissue.  Ruysch 
has  proved  that  these  pretended  glands  do  not  exist.  Hunter 
thought  that  this  secretion  was  produced  by  a  true  transuda- 
tion,  analogous  to  the  cadaverous  transudation  through  the 
areolae,  interstices  or  an  organic  porosities  of  the  tissue  of  the 
vessels.  Although  the  true  way  and  organic  mode  by  which 
the  perspiratory  and  other  secretions  are  performed,  are  not 
well  known,  we  may  at  least  affirm  that  they  differ  from  tran- 
sudation, which  takes  place  only  in  the  dead  body.  The  sero- 
sity  in  the  healthy  state  is  so  small  in  quantity,  as  to  be 
scarcely  perceptible,  and  hardly  capable  of  being  collected. 
Hewson  collected,  from  animals  suddenly  killed,  a  small  quan- 
tity of  the  liquid  that  humects  the  serous  membranes,  and  he 
saw  by  exposing  it  to  the  air  and  leaving  it  at  rest,  that  it 
coagulated  like  the  coagulable  lymph  of  the  blood.  He  was 
not  able  to  collect  the  serosity  of  the  cellular  tissue.  Bostock 
has  found  in  the  healthy  serosity  of  the  splanchnic  cavities, 
water,  albumen  in  less  proportion  than  in  serum,  incoagula- 
ble matter  and  salts.  Schwilgue  found  in  it,  albumen,  an  ex- 
tractive matter,  and  a  fatty  matter.  From  the  examination  that 
1  have  made  of  the  serosity  of  the  splanchnic  cavities,  it  seems 
to  me,  that  the  incoagulable  matter  is  gelatiniform  mucus, 
similar  to  that  found  in  the  coagulated  albumen  of  the  serum 
of  the  blood.  The  coagulability  of  the  healthy  serosity,  ob- 
served before  Hewson  by  Lower,  Lancisi,  and  Kaau,  has 
been,  on  the  contrary,  denied  by  Sarcone,Cotunnio  and  Gero- 
mini;*  I  believe  this  coagulability  always  exists  in  the  healthy 
state. 

§  233.  Of  all  the  serous  membranes,  those  of  which  we  now 
speak,  are  those  whose  functions  and  morbid  actions  are  the 
most  closely  connected  with  the  other  organic  phenomena, 
presenting,  however,  some  varieties;  thus  the  membrane  of 
the  testicle,  and  that  of  the  abdomen,  differ  greatly  in  this 
respect. 

§  234.  The  greater  part  of  what  has  been  said  respecting 
the  morbid  changes  of  the  whole  serous  system,  may  be  ap- 

*  tfaggio  sullagenesi,  e  cura  ddl"  idrope. — Cremona,  1816. 


180  GENERAL  ANATOMY. 

plied  to  these.  They  are  subject,  more  than  the  other,  to  some 
primitive  vices  of  conformation,  as  unnatural  openings,  ob- 
served in  some  cases  of  monstrosity,  of  which  they  all  may 
present  examples,  as  well  as  the  prolongations  or  appendages 
which  envelop  congenital  hernias  and  other  displacements. 

§  235.  Accidental  hernias  are  also  accompanied  by  an  altera- 
tion in  the  form  of  the  splanchnic  serous  membranes;  displaced 
parts  are  almost  universally  enveloped  by  a  hernia!  sac:  this 
sac  is  formed  by  the  serous  membrane  which  lines  their  pa- 
rietes,  and  which  the  viscera,  in  being  displaced,  push  before 
them. 

§  236.  Dropsy,  inflammation  and  its  effects,  false  membranes, 
adhesions,  accidental  productions,  either  analogous,  or  morbid, 
are  more  common  in  the  splanchnic  serous  membranes,  than 
in  the  other  species,  and  still  more  common  among  some  of 
their  own  number  than  in  others. 

§237.  Although  the  splanchnic  serous  membranes,  form  a 
tolerably  natural  group,  they  still  present  differences  which 
belong  to  special  anatomy;  the  arachnoid  besides,  differs  much 
from  the  others.  It  has  the  same  conformation  as  the  others, 
but  its  consistence  is  soft,  its  tenuity  extreme,  and  its  texture 
it  is  impossible  to  determine;  it  seems  homogeneous;  no  ves- 
sels are  to  be  found  in  it,  not  even  in  a  diseased  state.  The 
greater  part  of  the  morbid  phenomena  attributed  to  it,  takes 
place  in  the  subjacent  tissue  of  the  pia-mater;  it  seems,  in  fact, 
to  form  a  genus  by  itself. 


OF  THE  TEGUMENT ARY  MEMBRANES.          1S1 


CHAPTER  III. 


OP  THE  TEGUMENTARY  MEMBRANES. 

§  238.  These  membranes  are  those  which,  internally  as  well 
as  externally,  clothe  the  parts  that  are  exposed  to  contact  with 
foreign  substances.  They  are  also  called  compound  villous, 
or  folliculous  membranes,  on  account  of  the  numerous  parts 
which  enter  into  their  texture,  and  of  the  follicles  which  they 
contain  in  particular.  They  constitute,  next  to  the  cellular 
tissue,  of  which  they  are  a  modification,  more  or  less  com- 
pound, the  most  universally  extended  tissue  or  organ  in  the 
animal  kingdom;  they  are  the  first  parts  that  are  distinct  and 
figured  in  the  embryo;  it  is  on  them  and  by  them  that  all  the 
rest,  of  the  body  is  formed;  in  health  during  life,  they  are  the 
organs  of  the  most  essential  functions;  and  it  is  in  them  and 
by  them  that  absorption  and  extensive  secretion  takes  place; 
it  is  upon  them  that  all  foreign  substances  produce  impres- 
sions;  they  are  often  changed  by  disease;  it  is  on  them,  in 
fine,  that  most  therapeutic  agents  are  applied:  their  study  then 
is  of  the  highest  importance  to  the  physician. 

§  239.  Galen*  had  already  remarked,  that  besides  the  ex- 
ternal skin,  which  is  the  common  tegument  of  all  the  parts, 
there  is  a  thin  membranous  skin  which  clothes  the  internal 
parts;  several  anatomistst  had  already  indicated  the  continua- 
tion of  the  skin  into  some  of  the  natural  cavities,  andj  the 
analogy  of  the  mucous  membrane  with  the  epidermis;  Bonn§ 
had  already  described  in  detail,  the  continuation  of  the  skin 
with  the  internal  membrane,  into  all  the  openings  and  cavities; 

*  Of  the  therapeutic  method,  I.  xiv.  chap.  2. 

f  Casserius,  Pentaestheseion,  hoc  est,  de  quinque  sensibus,  liber. 

+  Glisson.  De  Guld,ventricub  etintestinis. 

§  D*  continuationibui,  membranarum. 


182  GENERAL  ANATOMY. 

zootomists  and  naturalists  had  also  observed  it,  as  well  as  the 
analogy  subsisting  between  these  two  parts  of  the  same  mem- 
brane, in  the  interval  of  which  all  the  rest  of  the  body  is 
placed.  Bichat  has  particularly  insisted  upon  this  continuity. 
M.  J.  B.  Wilbrand*  has  recently  given  an  exposition  in  detail 
of  the  cutaneous  or  tegumentary  system  in  all  its  divisions. 
M.  Hebreardt  has  described  the  transformation  of  the  skin 
into  mucous  membrane  and  vice  versa. 

§  240.  The  tegumentary  membranes,  throughout  their  whole 
extent,  have  common  characters,  of  which  it  is  necessary  to 
speak  first,  but  from  their  difference  of  situation,  texture  and 
functions,  they  are  divided  into  two  parts,  which  must,  subse- 
quently, be  separately  described:  these  parts  are,  the  mucous 
membrane  and  the  skin. 


SECTION  I. 

OF  THE  TEGUMENTARY  MEMBRANES  IN  GENERAL. 

§241.  The  teguments,  however  extensive  and  numerous 
they  may  seem,  form  one  single  and  same  membrane,  every 
where  continuous  to  itself  from  the  external  skin,  to  the  bot- 
tom of  the  last  ramifications  of  the  excretory  duct  of  the  most 
deeply  seated  gland :  this  membrane  consequently  has  im  mense 
breadth.  Its  situation  is  everywhere  external  or  superficial, 
inasmuch  as  it  is  situated  on  the  surfaces  of  the  body  whose 
limits  it  forms,  and  as  it  is  every  where  in  contact  with  substances 
foreign  to  the  organization;  but  one  portion  only  is  visible  ex- 
ternally, and  envelopes  the  whole  body,  while  the  other  part 
is  hidden,  and  lines  the  alimentary  canal,  which  traverses  the 
trunk  through  its  whole  length,  from  the  mouth  to  the  anus. 
We  may  hence  easily  conceive  the  figure  of  the  tegumentary 
membrane,  to  be  that  of  an  envelope,  and  of  a  canal  which 

*  Das,  huutsystem  in  alien  seinen  verzwergungen,  anatomisch,  physiol.  unit 
patJiol.  dargestellt.  Giessen,  1813. 

f  Mtm.  sur  fanalogie  qui  existe  entre  le  systeme  wiiqiieux  ft  dfrmoide,- 
Mem.  de  la  Soc.  med.  TfEmul  vol.  viii.  p.  153. 


OF  THE  TEGUMENTARY  MEMBRANES  IN  GENERAL.       183 

traverses  it,  continuous  with  each  other  to  the  two  extremities; 
or  rather  as  that  of  two  canals,  the  one  wide,  the  other  narrow, 
the  narrow  one  cased,  in  the  other,  and  continuous  to  the  two 
ends,  and  in  the  space  between  which  the  remainder  of  the 
body  is  lodged.  If  we  wished  to  employ  a  trivial  comparison, 
the  one  which  is  best  fitted  to  represent  this  disposition  is  that 
of  a  muff,  having  in  fact  two  surfaces  separated  by  a  layer  of 
intermediate  substance,  more  or  less  thick. 

§  242.  Besides  the  skin  and  the  mucous  membrane  of  the 
alimentary  canal,  continuous  with  each  other  to  the  two  orifices 
of  this  canal,  every  where  continuous  with  themselves,  and 
which  constitute  the  two  principal  parts  of  the  tegumentary 
membrane,  this  membrane  has  a  great  number  of  dependencies 
or  prolongations  more  or  less  extended  and  ramifiecj  in  the 
thickness  of  the  body:  such  are,  1st,  the  genital  and  urinary 
membranes,  which  are  prolonged  into  all  the  cavities  of  the 
organs  of  generation,  and  the  urinary  depuration;  2d,  the  pul- 
monary membrane  which  lines  all  the  divisions  of  the  bron- 
chiae :  3d,  the  membranes  which  line  the  excretory  ducts  of  the 
glands,  whether  they  terminate  in  the  mucous  membrane,  or 
like  those  of  the  mammae,  in  the  skin ;  4th,  those  of  the  nasal 
cavities,  of  their  sinuses,  and  posterior  nasal  fossae,  of  the  audi- 
tory canals,  of  the  tympanum,  of  the  mastoid  sinus,  and  of  the 
surface  of  the  eye. 

Among  these  prolongations,  all  mucous,  except  that  of  the 
external  auditory  canal,  which  is  cutaneous,  the  greater  por- 
tion of  them  terminate  in  and  are  appendages  or  prolongations 
of  the  mucous  membrane;  the  external  skin,  on  the  contrary, 
is  much  less  complicated  by  appendages  of  this  kind. 

§  243.  The  tegumentary  membrane  presents,  in  its  vast  ex- 
tent, differences  of  appearance,  of  texture,  and  of  function, 
which  might  induce  one  to  doubt  of  its  unity  and  continuity. 

The  skin  and  mucous  membrane  compared  with  each  other, 
at  the  first  glance,  seem  to  be  very  different;  but  in  the  animal 
series,  the  difference  is  gradually  effaced  in  the  more  simple 
animals;  it  is  also, generally,  but  slightly  marked  in  the  higher 
animals  which  inhabit  the  water.  In  the  human  foetus,  the 

difference,  though  real,  is  at  first  but  slightly  defined,     Even,. 
25 


1S4  GENERAL  ANATOMY. 

in  the  adult  we  see  the  skin  easily  transformed  into  mucous 
membrane,  and  the  latter  into  skin.  When,  for  example,  B 
part  of  the  surface  of  the  body,  is  for  a  long  time  substracted 
from  the  action  of  the  atmosphere,  as  has  been  seen  in  cases 
of  contractions,  where  the  leg  has  been  strongly  flexed  upon 
the  thigh,  as  is  often  seen  in  the  furrows  of  the  skin  of  very 
fat  children,  the  epidermis  softens  and  disappears,  and  the  skin 
at  last  secretes  mucus.  In  a  prolapsus  of  the  uretus,  on  the 
contrary,  we  see  the  mucous  membrane  of  the  vagina,  and  in  a 
prolapsus  of  the  anus,  natural  or  accidental,  that  of  the  rectum, 
thicken,  dry  and  assume  the  appearance  of  the  skin.  Finally, 
in  a  healthy  state,  in  many  parts,  we  see  the  skin  change  into 
mucous  membrane  gradually  and  insensibly;  this  is  the  case 
in  the  labia  pudendi,  the  prepuce,  anus,  mammae,  and  nostrils; 
it  is  only  in  the  eyelids  and  lips  that  the  line  of  demarcation 
appears  somewhat  defined.  There  is  then  no  real  interruption, 
but,  on  the  contrary,  there  is  a  perfect  identity  and  continuity 
between  the  two  principal  parts  of  the  tegumentary  mem- 
brane. 

§  244.  The  various  parts  of  these  two  principal  portions  of 
the  tegument,  present  also  tolerably  great  differences.  Those 
which  are  observed  between  the  skin  of  the  back  and  that  of 
the  eyelids,  between  those  of  the  cranium  and  of  the  papillary 
extremities  of  the  fingers,  for  instance,  are  tolerably  great,  but 
the}7  are  neither  absolute  nor  definite;  it  is  about  the  same  in 
the  mucous  membrane,  and  the  interruptions  which  have  been 
supposed  to  be  found  there,  are  merely  apparent,  as  will  be  seen 
hereafter,  (sec.  ii.)  The  differences  that  are  observed  between 
the  various  parts  of  the  mucous  membrane,  although  more 
strongly  marked  than  those  which  are  found  in  the  skin,  are 
not  more  real.  The  change  of  appearance  and  texture  is  ge- 
nerally gradual,  as  is  visible  in  the  excretory  ducts  where  the 
membrane  becomes  progressively  thinned  and  degraded,  if  we 
may  so  express  it,  but  in  an  insensible  manner.  If  we  com- 
pare the  membrane  of  the  frontal  sinuses,  with  that  of  the 
stomach,  we  will  certainly  find  great  differences  between 
them,  as  well  as  between  those  of  the  tongue  and  of  the 
uterus;  but  these  differences  are,  in  a  manner,  connected  by 


OF  THE  TEGUMENTART  MEMBRANES  IN  GENERAL.       185 

intermediate  gradations.  We  only  find  some  suddenly  marked 
differences,  in  parts  closely  approximated,  but  whose  func- 
tions are  very  different,  as  between  the  oesophagus  and  the 
stomach,  the  vagina  and  the  uterus;  but  even  there  as  well  as 
every  where  else,  they  are  only  varieties,  which  easily  reduce 
themselves  into  a  unique  type  of  organic  texture. 

§  245.  The  teguments  have  a  free  and  an  adhering  sur- 
face. The  first  is  turned  outwards  for  the  skin,  and  inwards 
for  the  mucous  membrane;  it  is  the  inverse  with  the  second. 
The  adhering  surface  corresponds  to  the  mass  of  the  body 
and  to  the  cellular  tissue  generally.  This  tissue  [139] 
forms  there  a  layer  more  or  less  dense,  more  or  less  thick; 
in  other  places  it  is  the  ligamentous  tissue,  or  the  fibrous  elas- 
tic tissue  which  lines  the  teguments;  in  a  considerable  por- 
tion of  their  extent,  they  are  lined  with  muscular  fibres. 

§  246.  The  tegumentary  membrane,  besides  the  great  ap- 
pendages and  excretery  ducts  of  the  glands  of  which  we  have 
spoken  [242],  has  an  innumerable  multitude  of  other  depres- 
sions, more  simple  and  a  great  deal  smaller,  that  have  been 
called  follicles,  loculae,  lacunae,  crypta,  simple  glands,  &c. 
These  follicles,*  at  first  observed  and  described  in  some  points 
of  the  teguments  by  various  anatomists,  and  afterwards  in 
all  the  parts  by  Malpighi,  Boerhaave,  Kaau,  and  many 
others,  exist  in  all  or  nearly  all  the  parts  of  these  membranes. 
The  follicles  are  round,  or  obround,  graniform,  of  a  variable 
size  and  generally  very  small:  they  are  situated,  in  part,  in 
the  thickness  of  the  membrane,  and  project  more  or  less  under 
its  adhering  surface.  They  have  generally  the  form  of  a 
little  ampulla,  whose  mouth  more  or  less  lengthened,  opens 
on  the  free  surface  of  the  membrane.  They  are  formed  by 
a  reflected  fold  of  this  membrane,  constituting  a  depression 
or  a  little  cul-de-sac.  They  constitute  the  pores  that  are  per- 
ceived on  the  surface  of  the  skin,  in  the  nose  particularly,  as 
well  as  the  granulations  that  line  and  elevate  the  mucous 

*  See  M.  Malpighi,  Epistola  de  structurd  glandularum,  etc.  in  op.  posthum. 
— Opusculum,  anatomicum,  de  fabrica  glandularum,  continens,  binas  episto- 
las. — Boerhaave  et  F.  Ruyschii,  etc.  in  op.  omn.  Ruyschii. — A.  Kaau.  Per' 
spiratio  dicta  ffippocrati,  ttc.  Cap.  xi.  xii.  et  xiii. 


186  GENERAL  ANATOMY. 

membrane  in  many  places;  the  cavity. of  these  follicles  is  ex- 
tremely small  in  comparison  with  the  thickness  of  its  parietes. 
They  are  formed  by  the  whole  membrane,  whether  still  pre- 
serving its  thickness,  or  having  it  increased  or  diminished. 
They  are  surrounded  by  an  immense  number  of  minute  vas- 
cular ramifications.  The  majority  of  these  little  ampulla  are 
simple,  distinct,  and  placed  more  or  less  apart  from  each  other; 
but  in  certain  parts  of  the  skin,  and  of  the  mucus  membranes 
especially,  follicles  are  found  variously  assembled  and  com* 
posed.  Besides  these  follicles  of  which  we  are  speaking,  the 
tegumentary  membranes,  and  chiefly  the  internal  one,  pre- 
sents many  depressions,  whose  orifice  is  as  large  as  the  bottom, 
and  which  are  called  alveolar,  and  both  the  one  and  the  other 
present  a  great  number  of  little  tapering,  or  infundibuliform 
depressions.  The  follicles  differ  from  each  other,  also,  in  the 
nature  of  the  liquid  they  secrete  and  contain :  those  of  the  skin 
are  called  sebaceous  follicles,  and  those  of  the  internal  tegu- 
ment, mucous  follicles,  so  styled  on  account  of  the  liquid  they 
furnish;  those  of  the  mucous  membranes  in  the  vicinity  of  the 
skin  are  almost  of  a  mixed  nature,  participating  of  both. 

§  247.  The  teguments  have  a  foliated  texture;  throughout 
a  great  part  of  their  extent  they  are  evidently  formed  of  two 
layers,  the  dermis  and  the  epidermis ;  in  many  places,  another 
tolerably  compound  layer  is  found  between  the  two  first ;  and 
in  a  great  number  of  parts,  there  are,  besides,  appendages,  or 
productions,  arising  from  the  free  surface  of  the  membrane. 

§248.  The  dermis,  whatever  differences  it  presents  in  the 
two  teguments  and  in  their  divisions,  is  always  the  deepest 
part  of  them,  the  thickest,  that  which  forms  their  base,  and  on 
the  surface  of  which  the  others  are  placed.  It  is  formed  of  a 
layer  of  fibrous  cellular  tissue,  more  or  less  dense,  furred,  and 
leaving  interstices  through  which  pass  various  other  parts. 

§249.  Blood-vessels,  lymphatics  and  nerves,  more  or  less 
numerous,  are  distributed  and  ramified  through  the  thickness 
of  the  dermis  and  on  its  supernces,  where  they  form  inequali- 
ties called  papillae,  villosities,  vascular  buds,  and  which  will 
be  more  exactly  defined  and  described,  when  speaking  of 
each  of  the  two  teguments. 


OF  THE  TEGUMENTARY  MEMBRANES   IN  GENERAL.       1ST 

§  250.  The  surface  of  the  dermis  is  covered  with  a  layer 
more  or  less  distinct,  according  to  the  part  of  the  tegument, 
and  which  is  called  the  mucous  or  reticulated  body;  it  is  cel- 
lular tissue,  in  a  semi  liquid,  or  imperfectly  organized  state, 
in  which  the  most  minute  divisions  of  the  white  vessels  arise 
or  terminate;  this  layer,  otherwise  very  compound,  is  the  seat 
of  the  colour,  and  that  of  the  horny  incrustations  which  cover 
the  teguments  in  some  places.  This  layer  is  less  distinct  in 
the  mucous  membranes  than  in  the  skin* 

§  251.  Finally,  the  epidermis  is  the  last  essential  part  of 
the  tegumentary  membranes,  that  which  forms  their  free  sur- 
face; it  is  an  albuminous  layer  excreted  on  the  surface  of  the 
mucous  body.  In  many  parts  of  the  mucous  membranes,  the 
epidermis  is  not  distinct  and  seems  to  be  substituted  by  mucus. 
Independently  of  this,  and  as  regards  the  chemical  nature  of 
the  matter,  there  is  much  resemblance  between  the  epidermis 
and  mucus. 

§  252.  Several  parts  of  the  tegumentary  membranes,  are 
provided  with  salient  appendages  on  their  free  surface:  those 
are,  the  nails  and  hairs  for  the  skin;  and  the  teeth,  for  the 
mucous  membrane. 

§  253.  By  decoction,  the  teguments  are  resolved  almost  en- 
tirely into  gelatine.  The  very  different  colours  of  the  tegu- 
ments depend  partly  upon  that  of  the  blood  and  partly  upon 
a  colouring  matter  secreted  from  it,  in  the  mucous  body.  Their 
very  variable  density,  is  nearly  intermediate  between  that  of 
the  cellular,  ligamentous,  and  elastic  tissues.  Their  elasticity 
is  tolerably  well  marked.  They  possess,  also,  a  very  great, 
but  slow  extensibility  and  retractability,  Their  formative 
power  is  highly  developed.  Although  their  irritability  is 
much  less  evident  than  that  of  the  muscles,  they  possess  a 
large  share  of  it.  They  are  the  essential  organ  of  sensibi- 
lity. 

§  254.  The  organic  action  or  function  of  the  tegumentary 
membrane  is  very  important,  very  complex  and  different  in 
the  different  parts  of  that  membrane.  As  a  tegument  or  en- 
velope of  the  mass  of  the  body,  internal  as  well  as  external, 
it  constitutes  a  barrier  through  which  must  pass  inwardly 


188  GENERAL  ANATOMY. 

from  without,  all  the  foreign  substances  that  enter  into  the 
body  to  become  portions  of  it,  and  from  within  outwardly,  all 
those  which  after  having  been  parts  of  it,  become  foreign  to  it; 
these  substances  and  all  others  which  are  in  contact  with  the 
tegument,  determine  impressions  on  it;  thus  this  membrane  is 
an  organ  of  defence  or  protection  of  more  or  less  efficacy, 
against  the  action  of  external  bodies ;  it  is  the  organ  of  external 
absorptions  and  secretions,  i.  e.  of  those,  the  matter  of  which  is 
taken  from,  or  deposited  without ;  it  is  the  organ  of  all  external 
sensations,  and  of  the  feeling  of  want  and  appetite;  and,  finally, 
through  its  appendages,  it  is  sometimes  an  organ  of  offence  or 
aggression.  But  the  functions  of  this  membrane  vary  in  the 
different  regions,  according  to  the  nature  of  its  texture ;  thus 
the  mucous  membrane  is  better  fitted  for  absorption  and  secre- 
tion than  the  skin,  while  the  latter  is  more  adapted  to  receive 
sensations  and  defend  the  body  than  the  former.  Some  parts  are 
specially  fitted  for  sensation,  and  even  for  this  or  that  sensa- 
tion, others  for  absorption,  some  for  excretion,  others  for 
generation,  respiration,  &c. 

§  255.  The  immense  extent  of  the  tegumentary  membrane, 
the  number  and  importance  of  the  functions  of  which  it  is  the 
seat  and  instrument,  render  its  consideration  a  matter  of  much 
importance,  both  in  health  and  disease.  Between  the  two 
principal  parts  of  which  it  is  composed,  there  exists  the  most  in- 
timate relation,  which  in  certain  respects,  was  perceived  by  the 
most  ancient  observers,*  who  knew  that  the  abundance  of  the 
mucous  secretion  is  generally  in  an  inverse  ratio  to  that  of  the 
cutaneous  secretion.  Observation  has  taught  us  that  a  healthy 
state  of  the  skin  coincides  with  a  similar  condition  of  the  mu- 
cous membrane,  and  that,  for  instance,  those  persons  whose 
skins  are  very  white,  and  of  a  fine  delicate  texture,  are  very 
liable  to  diseases  of  the  skin  and  mucous  membrane,  and 
particularly  to  discharges  from  these  two  membranes.  It 
has  also  taught  us  that  every  part  of  the  skin  sympathizes  with 
the  whole  mucous  membrane,  and  with  this  or  that  part  of  it 
especially.  There  also  exists  an  equally  intimate  relation  be- 

»  XS/AM;  VUMSTM.  innOKPATOT2,  TUV  V/cT^c.  B/3-X.  f. 


OF  THE  TEGUMENTARY  MEMBRANES  IN  GENERAL.   189 

tween  the  teguments  and  the  mass  of  the  body,  and  vice  versa; 
a  relation  which  is  daily  rendered  obvious  by  observation,  one 
which  morbid  causes  are  continually  putting  in  action,  from 
the  observation  of  whose  symptoms  the  practitioner  endea- 
vours to  profit. 

§  256.  We  have  already  stated  that  the  embryo  is  wholly 
formed  on  these  membranes:  the  vitellar  or  intestinal  mem- 
brane is  the  first  that  appears  in  the  egg;  it  is  by  its  prolonga- 
tion towards  the  stomach,  and  towards  the  anus  that  the  intes- 
tine is  formed.  The  second  apparent  part  is  the  allantoid  or 
the  vesical  membrane,  by  the  extension  of  which  the  urinary 
passages  and  genital  organs  are  formed.  The  external  skin  is 
next  produced:  at  first  widely  open  in  front  of  the  trunk,  it 
closes  in  the  median  line  of  the  abdomen,  and  finalljT,  round 
the  umbilicus.  In  the  two  sexes  there  is  a  great  difference  of 
conformation  in  the  genito-urinary  portion  of  the  teguments, 
and  a  difference  of  development  in  that  of  the  excretory  ducts 
of  the  mammae.  Besides  this,  there  is  a  difference  of  colour- 
ing and  of  thickness  in  the  external  skin.  These  differences 
are  well  marked  in  the  various  races  of  the  human  species,  and 
are  also  visible  in  individuals. 

§257.  Morbid  changes  are  very  numerous  in  the  different 
parts  of  the  tegumentary  membrane.  Accidental,  cutaneous, 
and  mucous  productions  frequently  occur.  Reproductions  of 
the  tegument  or  cicatrices,  are  seen  daily.  Vices  of  conforma- 
tion, alterations  of  texture  and  functions,  accidental  produc- 
tions, analogous  or  not  to  the  healthy  tissue,  transformations 
of  tissue,  &c.  are  also  frequently  observable  in  the  teguments; 
but  their  description  will  be  better  placed  after  that  of  each  of 
these  membranes;  the  same  observation  will  apply  to  their 
cadaverous  alterations. 

§  258.  The  accidental  teguments,  on  the  contrary,  should 
be  described  here,  because,  on  the  one  hand,  their  production 
is  very  analogous  in  both  teguments;  and  on  the  other,  because 
in  the  production  of  an  external  cicatrix,  the  new  tissue,  during 
one  period  of  its  formation,  resembles  the  mucous  membrane, 
and  at  a  later  one,  the  skin;  and  finally,  because  in  some  cases 
we  find  the  appearance  and  texture  of  the  skin  in  one  part,  and 


190  GENERAL  ANATOMY. 

that  of  the  mucous  membrane  in  another  of  the  same  produc- 
tion. Such  as,  for  instance,  the  membranes  of  fistulas. 

Every  time  that  either  by  mechanical  lesion,  by  the  effects 
of  cauterization,  gangrene,  or  ulceration,  there  is  a  destruction 
of  the  teguments,  or  even  of  the  subjacent  parts  to  a  greater  or 
less  depth,  a  tegument  is  always  produced  similar  to  the  one 
destroyed,  or  at  least  very  analogous  to  it,  and  similar  in  its 
whole  extent,  whatever  be  the  diversity  of  denuded  parts 
that  are  to  be  reclothed  by  it.  After  the  primitive  phenomena, 
varying  according  to  the  causes  of  the  injury,  there  is  a  series 
of  secondary  ones  always  similar:  they  are  1st,  the  production 
of  a  plastic  layer  like  that  of  agglutination ;  2d,  the  formation  of 
buds  or  granulations,  and  the  secretion  of  pus;  3d,  the  cessa- 
tion of  this  secretion,  and  the  completion  of  the  cicatrix.  The 
phenomena  of  cicatrization  commence  by  the  deposition  of  a 
plastic  layer  similar  to  that  which  constitutes  the  false  mem- 
branes. This  layer  at  first  is  inorganic,  but  soon  becomes  or- 
ganized,covered  with  little  red, conical  granulations, and  consti- 
tuting then  the  membrane  of  the  fleshy  granulations;  this  mem- 
brane is  cellular,  vascular,  very  contractile,  sensible,  absorbent, 
secreting  pus,  apt  to  be  destroyed  by  ulceration,  and  quickly 
reproduced.  This  membrane  is  continually  contracting,  the 
secretion  of  pus  gradually  diminishes,  and  finally  ceases,  when 
it  becomes  covered,  either  with  a  distinct  epidermis,  or  with 
mucus,  according  to  the  part,  and  constitutes  a  new  tegument, 
very  analogous,  and  sometimes  absolutely  similar  to  the  old 
one.  This  membrane,  however,  besides  some  slight  anatomi- 
cal differences,  is  much  more  susceptible  of  ulceration  than  the 
primitive  teguments. 

§259.  In  abscesses,  and  particularly  in  chronic  abscesses,  a 
membrane  is  formed  which  circumscribes  the  pus,  and  which 
strongly  resembles  the  mucous  membrane;  this  resemblance 
is 'still  greater,  when  the  abscess  is  opened  and  remains  the 
source  of  a  fistulous  ulcer;  it  is  the  same  with  that  kind  of  ul- 
cers kept  up  by  necrosis,  or  the  presence  of  foreign  bodies;  it 
is  also  the  same  with  true  fistulas,  or  the  accidental  canals 
which  arise  from  a  natural  mucous  cavity.  In  every  case,  the 
passage  is  lined  through  its  whole  extent  by  a  fungous,  soft, 


OF  THE  MUCOUS  MEMBRANE.  191 

mucous  membrane,  discovered  by  Hunter,  in  fistula  in  ano. 
At  its  orifice  in  the  skin,  if  it  terminates  on  that  surface,  the 
mucous  canal  of  the  fistula,  to  a  certain  depth,  has  a  distinct 
epidermis,  which  is  continued  with  that  of  the  skin. 


SECTION  II. 

OF  THE  MUCOUS  MEMBRANE. 

§  260.  The  internal  tegumentary,  or  mucous  membrane  has 
received  the  latter  name,  at  first  in  the  nasal  fossae  (^v|a,  nos- 
trils)  on  account  of  the  mucus  (pvfr pituita]  it  produces.  It 
constitutes  a  humid  tegument  that  clothes  all  the  cavities  com- 
municating externally,  all  of  which  receive  or  eject  foreign 
substances.  Regarded  at  first  as  the  particular  internal  mem- 
brane of  each  hollow  organ,  and  having  no  other  name,  after- 
wards called,  villous  or  fungous,  pulpy,  porous  villoso-papilla- 
ry,  in  the  alimentary  canal,  pituitary,  or  mucus  in  the  nose 
and  throat,  anatomists  were  not  long  in  discovering  follicles  in 
nearly  all  its  parts,  which  caused  it  to  receive  the  generic  ap- 
pellation of  glandular,  and  in  remarking  the  resemblance  of 
the  nasal  and  intestinal  mucus,  to  the  unctuous  humour  of  the 
trachea  and  bronehiae,  and  even  the  analogy  of  mucus  to  the 
epidermis;  from  this  moment  the  identity  of  the  various  parts 
of  this  membrane  was  known.  Pathologists,  M.  Pinel  in  par- 
ticular, had  already  remarked  this  in  treating  of  catarrh.  No 
general  and  satisfactory  description  of  this  membrane,  how- 
ever, had  been  given  until  that  of  Bichat.*  Anatomists  and 
pathologists,  have  since  generally  agreed  in  adopting  his  ideas 
on  this  subject,  Gordon  excepted,  who  finds  too  many  essential 
differences  between  the  various  mucous  membranes,  to  include 
them  in  one  common  description. 

§261.  The  mucous  membrane  forms  an  internal  tegument 
to  all  the  cavities  that  open  externally;  its  more  important  por- 
tion clothes  the  whole  alimentary  canal  from  the  mouth  to  the 

*  TraiM  det  membranes.  Paris,  an.  viii. 
26 


192  GENERAL  ANATOMY. 

anus;  the  remainder  constitutes  prolongations  or  appendages 
prolonged  in  a  cul-de-sac,  more  or  less  extended  and  rami- 
fied in  the  mass  of  the  body,  and  their  orifice  terminating 
either  on  the  external  or  internal  skin.  It  thus  forms  an  im- 
mense internal  tegument,  of  much  greater  extent  than  the 
skin. 

§262.  The  mucous  membrane,  like  the  skin,  presents  an 
adhering  and  a  free  surface;  the  adhering  or  external  surface 
is  generally  covered  with  a  particular  layer  of  fibrous  cellular 
tissue,  which  has  been  named  by  Ruysch  and  other  anatomists, 
the  nervous  membrane,  which  Albinus  and  Haller  have  de- 
monstrated to  consist  of  cellular  tissue,  and  which  Bichat  has 
called  the  sub-mucous  cellular  tissue.  This  tissue  is  close, 
fibrous,  white,  never  contains  fat,  and  rarely  any  infiltrated 
serosity;  it  is  traversed  by  a  great  number  of  small  branches 
of  vessels  and  nerves.  Several  anatomists  have  assimilated 
it  to  the  dermis  of  the  skin.  However  this  may  be,  it  is  to 
it,  that  the  hollow  organs  in  a  great  measure  owe  their  solidity. 
The  mucous  membrane  is  moreover  lined  throughout  the  ex- 
tent of  its  principal  canal  and  of  several  of  its  divisions,  by  a 
muscular  plane,  a  kind  of  internal  muscular  coat  analogous  to 
those  muscles  we  have  denominated  sub-cutaneous;  in  some 
places  it  is  an  elastic  tissue  that  covers  the  mucous  membranes, 
visible  in  the  trachea  and  the  excretory  ducts;  in  others,  a 
true  ligamentous  tissue,  as  the  periosteum  of  the  nasal  fossae, 
of  the  sinuses,  of  the  palate,  of  the  alveolar  processes,  lines 
this  membrane,  making  of  it  a  fibro-mucous  membrane. 

§  263.  The  free  surface  of  the  mucous  membrane  presents 
valvuli,  folds  and  wrinkles,  formed  by  the  doubling  of  the 
whole  thickness  of  the  membrane.  The  valvuli  are  formed 
by  folds  of  the  mucous  membrane,  by  the  sub-mucous  tissue, 
and  by  muscular  fibres  contained  in  the  fold;  this  is  the  case 
in  the  pylorus,  the  mouth  of  the  jejunum,  in  the  colon,  the  ve- 
lum palati,  the  orifice  of  the  larynx,  &c.  The  folds  contain, 
in  their  thickness,  sub-mucous  tissue  only,  but  they  always 
remain,  like  the  valvuli,  and  are  never  effaced :  such  are  the 
numerous  folds  of  the  small  intestine  which  are  called  valvuli 
conniventes;  the  wrinkles  on  the  contrary  are  accidental  or 


OF  THE  MUCOUS  MEMBRANE.  193 

momentary  folds,  in  which  the  mucous  membrane  is  in  re- 
serve for  future  dilatations  of  the  organs,  or,  which  depend 
upon  the  expansion  and  subsequent  contraction  of  the  organ, 
by  which  the  mucous  membrane  is  made  to  exceed  the  mus- 
cular membrane:  such  are  the  longitudinal  wrinkles  of  the 
oesophagus  and  trachea,  the  irregular  wrinkles  of  the  stomach 
when  contracted,  the  regular  wrinkles  of  the  vagina  and  of 
the  neck  of  the  uterus,  &c. 

§  264.  The  free  surface  of  the  mucous  membrane  presents 
also  cavities  or  depressions  of  various  kinds,  and  papillary 
and  villous  projections.  But  these  various  objects,  although 
generally  dispersed  throughout  the  membrane,  do  not  exist, 
or  at  least  are  not  equally  apparent  in  all  points  of  its  extent. 
Infundibuliform  cellular  or  alveolar  depressions  are  found  on 
the  surface  of  the  membrane:  they  are  found  at  the  maximum 
of  their  development  in  the  second  stomach  of  the  ruminantia, 
which  on  this  account  is  called  the  honeycomb;  they  exist  also, 
but  much  smaller  and  more  microscopical,  in  a  great  part  of  the 
alimentary  canal,  and  particularly  in  the  oesophagus,  stomach, 
and  the  colon  of  man,  where  they  were  perceived  and  pointed 
out  by  Fordyce  and  Hewson,  and  described  and  figured  by 
M.  Ed.  Home. 

§265.  The  follicles*  only  differ  from  these  alveolar  depres- 
sions in  having  a  very  small  orifice,  a  neck  more  or  less  pro- 
longed, and  a  bottom  resembling  an  ampulla,  placed  in  the 
sub-mucous  tissue  where  they  project.  They  are  formed  by 
a  reflection  of  the  membrane,  strengthened  externally  by- 
dense  cellular  tissue,  and  provided  with  numerous  small  ves- 
sels. They  are  every  where  to  be  found,  their  number,  how 
ever,  varies  according  to  the  part ;  they  are,  in  general,  very 
small,  but  they  vary  also  greatly  in  size.  Some  are  simple 
and  separate;  others  terminate  in  a  common  canal  of  which 
they  arc  as  it  were  branches;  others  again  end  in  a  common 
and  dilated  orifice,  called  a  lacuna;  such  is  the  hole  at  the  base 
of  the  tongue,  the  Iacuna3  of  the  urethra,  rectum,  &c.;  another 

*  Peyer.  dc  Gltmdulis  intestinalium.     Amstel.   1681. — T.  C.  Brunner.  dc 
Glandulis  duodeni.    Francof.  1715. 


194  GENERAL  ANATOMY. 

set  are  aggregated,  as  the  caruncula  lachry mails,  the  aryte- 
noid  gland,  the  aggregated  glands  of  the  ilium,  &c.;  finally, 
others  are  compound  and  have  multiplied  lacuna  or  ramified 
ducts,  and  greatly  resemble  glands:  such  are  the  tonsils,  the 
molar  glands,  the  prostate,  the  glands  of  Cowper,  &c. 

§  266.  The  little  eminences  called  papilla?  or  villosities  that 
are  seen  on  the  free  surface  of  the  mucous  membrane  appear 
to  be  designed,  like  the  depressions  of  which  we  have  been 
speaking  and  to  which,  in  number,  they  are  in  an  inverse 
ratio,  to  increase  the  surface;  but,  in  the  one  as  well  as  the 
other  of  these  dispositions,  the  texture  and  functions  of  the 
membrane  are  remarkably  modified.  These  eminences,  called 
villosities,  in  consequence  of  the  comparison  drawn  by  Fallopius 
between  the  internal  membrane  of  the  intestines  and  velvet, 
and  named  papillae,  on  account  of  their  supposed  resemblance 
to  a  button  or  nipple,  do  not  essentially  differ  with  each  other; 
both  are  projections  of  the  membrane  more  or  less  fine,  and 
the  greater  part  hardly  visible  to  the  naked  eye. 

The  most  voluminous  of  these  elevations  are  called  papillae, 
such  are  those  that  fill  the  cavity  of  the  teeth,  commonly 
called  their  pulp;  those  smaller  ones  that  bristle  the  two  ante- 
rior thirds  of  the  tongue,  and  those,  still  smaller,  that  are  per- 
ceived on  the  gland  of  the  penis,  of  the  clitoris,  &c.  These 
elevations  belong  to  the  corium  of  the  mucous  membrane, 
furnished  in  these  places  with  a  great  number  of  nervous 
threads  and  small  branches  of  blood-vessels,  among  which  the 
little  veins  present  an  erectile  disposition.  In  parts  provided 
with  papillae,  the  mucous  membrane  is  furnished  with  a  dis- 
tinct epidermis,  called  epithelium,  on  account  of  its  covering 
the  papillae. 

§  267.  The  villosities,  whose  existence  is  very  general,  but 
which  are  nowhere  more  numerous,  larger,  or  more  apparent, 
than  in  the  pyloric  half  of  the  stomach,  the  small  intestine, 
and  in  the  beginning  of  it  in  particular,  are  still  smaller  than 
the  papillae. 

These  villosities,  which  may  with  justice  be  styled  the  radi- 
cles of  animals  ^are,  little  foliaceous  prolongations  of  the  internal 
membrane  of  the  digestive  canal,  whose  form  and  length  vary 


OF  THE  MUCOUS  MEMBRANE.  195 

in  the  different  parts  of  it,  and  which,  the  difference  of  volume 
excepted,  may  be  compared  to  the  transverse  folds  or  the  val- 
vuli  conniventes  of  the  intestines.  The  villi*  perceived  by 
Fallopius  and  Azelli,  described  and  represented  by  Helvetius, 
Lieberkuhn,  Hedwig,  Rudolph,  Meckel,  Buerger  and  several 
other  anatomises,  are  found,  particularly,  in  the  small  intestine; 
they  are  not  so  long  and  are  less  numerous  in  the  stomach 
and  colon.  To  have  a  fair  view  of  them,  it  is  necessary  to 
take  a  portion  of  the  intestine  unchanged  by  putrefaction,  to 
open  it  carefully,  to  moisten  it  with  drops  of  water  until  the  sur- 
face is  completely  covered  by  it,  and  then  to  examine  it  through 
a  lens,  which  will  increase  its  diameter  about  forty  times. 

§  268.  To  make  this  examination  as  well  as  others  analogous 
to  it,  I  have  used,  with  much  advantage,  a  little  apparatus 
composed  of  a  glass  sphere  of  small  diameter,  open  on  one 
fourth  of  its  surface,  and  of  an  operculum  a  little  smaller  than 
the  opening,  and  of  a  thin  layer  of  wax.  The  part,  to  be  exa- 
mined is  to  be  fixed  on  the  wax  with  small  pins,  it  is  then 
plunged  into  water  with  the  open  sphere,  which  is  to  be  filled 
with  that  liquid,  and  afterward,  placed  on  the  operculum.  The 
apparatus  is  now  withdrawn,  and  the  object  to  be  examined 
is  thus  covered  by  a  little  lenticular  mass  of  water,  which  aug- 
ments its  diameter. 

§  269.  Examined  in  either  of  these  two  ways,  the  villi  ap- 
pears neither  conical,  cylindrical,  canaliform,  nor  enlarged  at 
the  summit,  as  many  authors  have  described  them,  but  rather 
in  the  form  of  little  leaves  or  laminulse,  whose  numbers  are  so 
great  as  to  convey  the  appearance  of  a  luxuriant  grass-plot. 
These  little  leaves,  variously  bent  and  consequently  seen  in 
various  aspects,  appear  to  have  different  forms:  neither  are 
they  everywhere  the  same:  those  of  the  pyloric  half  of  the 

*  See  among  other  authors,  Helvetius.  Mem.  de  fAcademie  des  Sciences. 
Paris,  1721.— T.  N.  Lieberkuhn.  de  Fair,  et  ad.  Fillos.  Intest.  horn.  Lug-d. 
Bat.  1744,  4to. — R.  A.  Hedwig.  Disquis.  Ampull. — Lieberkuhnii.  physico- 
micros.  Lips.  1794,  4to. — C.  A.  Rudolphi.  in  Reils  Archiv.  der  physioL  IV. 
et  Anal,  physiol.  abhandl.  Berol.  1802. — J.  F.  Meckel  in  Deutches  Archiv. 
fur  die  physioL  III. — H.  Buerger.  Examen.  micros.  Villos.  intestin.  cum 
iconibus.  Halae,  1819 — 8vo. 


196  GENERAL  ANATOMY. 

stomach  and  of  the  duodenum,  broader  than  they  are  long,  con- 
stitute little  blades;  those  of  the  jejunum,  long  and  narrow, 
are  better  entitled  to  the  name  of  villi,  and  near  the  end  oi' 
the  ilium,  as  well  as  in  the  colon,  where  they  scarcely  project 
at  all,  they  again  become  laminae.  The  villi  are  semi-dia- 
phanous, their  surface  is  smooth,  and  we  can  neither  perceive 
on  their  surface  the  openings  which  have  been  admitted  with- 
out ever  being  able  to  agree  as  to  their  number,  nor  in  their 
thickness,  the  cellular  ampullae,  nor  vascular  texture  that  has 
been  described;  we  only  perceive  in  their  gelatiniform  sub- 
stance, microscopic  globules  arranged  in  a  linear  series,  and 
at  their  base,  small  branches  of  blood-vessels  and  lymphatics 
of  an  excessive  tenuity. 

§  270.  The  anatomical  texture  and  composition  of  the  mu- 
cous membrane  present  many  varieties  or  differences,  in  differ- 
ent parts.  The  foliated  disposition  can  not  be  demonstrated 
in  all  parts  of  the  membrane,  and,  on  the  contrary,  manifestly 
exists  in  some  points  of  it. 

In  the  greater  part  of  its  extent  the  membrane  consists 
solely  in  one  spongy  tissue,  more  or  less  soft  and  very  varia- 
ble as  to  thickness.  With  respect  to  this  we  must  observe, 
that  in  the  very  young  foetus,  and  in  the  inferior  animals  of 
the  series,  the  external  skin  itself  presents  this  character  of 
simplicity.  As  to  the  thickness,  it  diminishes  successively 
from  the  gums,  palate,  nasal  fossa?,  stomach,  intestines,  biliary 
and  urinary  bladders,  to  the  sinuses  and  divisions  of  the  ex- 
cretory ducts,  where  its  tenuity  becomes  extreme.  It  is  in 
this  essential  part  of  the  membrane  and  at  its  surface,  that  the 
last  divisions  of  the  vessels  ramify;  it  is  from  its  free  surface 
that  arise  the  villosities. 

§  171.  But  slight  traces  of  a  distinct  layer  of  the  mucous 
body  is  to  be  found  in  it,  unless  we  regard  as  such,  the  layer 
of  coagulable  fluid,  that  separates  the  papilla?  of  the  tongue 
from  the  epidermis,  or  consider  the  gelatiniform  surface  of  the 
villosities  as  belonging  to  it,  or  admit  as  proofs  of  its  exist- 
ence the  ephelides  or  variously  coloured  spots  that  are  some- 
times found  in  the  teguments  of  the  glans  penis  and  of  the 
vulva,  as  well  as  the  accidental  imperfect  horny  productions, 


OP  THE  MUCOUS  MEMBRANE.  197 

which  are  still  more  frequently  observed  in  the  same  parts  in 
a  form  called  warts. 

The  existence  of  the  epidermis  is  much  more  manifest,  with- 
out, however,  being  general. 

§  272.  The  epidermis  or  epithelium  is  very  apparent  at  the 
orifices  of  the  mucous  cavities;  it  is  less  so  in  their  deeper 
parts,  and  finally  ceases  to  be  apparent.  Does  it  however 
exist  there?  Haller  and  others  have  thought  that  it  does, 
and  that  the  accidental  membraniform  excretions  are  a  proof 
of  it.  Every  pathologist  of  the  present  day,  knows  that  such 
excretions  are  generally  the  result  of  a  plastic  inflammation, 
and  sometimes  of  eschars.  The  same  conclusion  has  been  at- 
tempted to  be  drawn  from  the  formation  of  an  artificial  anus, 
accompanied  with  a  retroversion  of  the  intestine  in  which  the 
epidermis  becomes  very  apparent;  but  this  only  proves  that 
the  free  surface  of  the  mucous  membrane  is  covered  with  a 
substance  which  is  very  analogous  to  the  epidermis,  and  which 
is  very  much  disposed  to  undergo  this  transformation.  By 
depending  upon  what  observation  teaches,  and,  by  the  use  of 
dissection,  decoction  and  putrefaction,  to  separate  the  epithe- 
lium, it  is  found  very  distinct  as  far  as  into  the  esophagus,  ter- 
minating suddenly  at  the  union  of  this  canal  with  the  stomach; 
it  is  also  very  distinct  in  the  vagina,  terminating  all  at  once 
on  the  lips  of  the  os  uteri,  interruptions  long  ago  known, 
and  erroneously  adduced  by  some  modern  writers  as  proofs 
of  the  interruption  of  the  mucous  membrane  itself.  In 
other  parts,  as  in  the  nasal  fossae  and  the  inferior  extremity 
of  the  alimetary  canal,  their  diminution  of  the  appearance  of 
the  epithelium  is  gradual,  insensible,  and  it  is  impossible  to 
assign  its  limits  with  exactness.  In  those  places  where  it  is 
distinct,  it  dips,  becoming  thinner  and  thinner,  into  the  folli- 
cles, where  it  is  lost.  In  places  deprived  of  a  distinct  epithe- 
lium, the  free  surface  of  the  membrane  is  covered  with  a 
mucous  varnish,  which  from  the  time  of  Vesalius  and  even 
of  Rhazes,  has  been  compared  to  the  covering  or  tinning  of 
vessels;  and  of  which  Glissen  has  remarked,  at  least  with  re- 
gard to  its  functions,  the  analogy  with  the  epidermis. 

§273.   The  cellular  tissue  which  forms  the  corium  of  the 


198  GENERAL  ANATOMY. 

mucous  membrane,  has  not  a  regularly  aereolar  disposition 
like  that  of  the  cutaneous  dermis;  it  is  rather  spongy  or 
fungous.  Blood-vessels  and  lymphatics  abound  in  it.  Its 
nerves  generally  arise  from  the  great  sympathetic  and  the  par- 
vagum:  at  all  the  natural  orifices,  the  mucous  membrane  is 
supplied  with  nerves  from  the  medulla  spinalis. 

§  274.  The  colour  of  the  mucous  membrane  varies  from 
white  to  red,  and  besides  the  intermediate  shades,  it  presents 
other  differences  of  colour.  This  colour  is  owing,  at  least  in 
a  great  measure,  to  the  blood  which  circulates  through  its 
thickness,  for  asphyxia  or  syncope,  either  imparts  a  brown  tint 
to,  or  instantly  deprives  of  all  colour,  the  parts  of  this  mem- 
brane which  from  their  situation  are  visible.  Its  consistence 
is,  in  general,  soft  and  fungous-like.  It  varies  greatly  in  thick- 
ness, and  its  tenacity  is  moderate.  The  mucous  membrane 
is  quickly  changed  by  putrefaction,  and  the  sub-mucous  tissue 
still  more  so,  for  it  is  then  very  easily  detached.  Whether 
it  is  susceptible  of  being  converted  into  leather  by  the  action 
of  tanning,  is  not  known. 

§  275.  Its  force  of  formation  is  highly  developed;  when  de- 
stroyed, it  is  soon  reproduced  with  all  the  characteristics  of 
the  natural  tissue.  It  is  slightly  irritable  and  possesses  a 
higher  degree  of  tonic  contractility  than  the  cellular  tissue. 
Its  sensibility  is  vague  and  obscure  throughout  the  greater 
part  of  its  extent.  Even  when  inflamed  it  does  not,  general- 
ly, occasion  much  pain.  It  is  very  sensible  at  the  natural 
openings;  and  at  the  entrance  of  the  alimentary  and  perspira- 
tory canals,  it  is  the  seat  of  a  special  sensibility. 

§  276.  Its  organic  actions  or  functions  are: 

1st.  Absorption,  which  is  very  active  and  general,  and  of 
which  the  villi  are  the  most  active,  but  not  the  only,  agents. 

2d.  Secretion,  which  is  perspiratory  and  follicular,  and 
whose  products,  differing  according  to  the  parts,  are  all,  how- 
ever, known  by  the  name  of  mucosities. 

3d.  Movements  of  tonic  contraction,  strengthened  in  many 
places  by  the  action  of  the  elastic  tissue  and  even  by  that 
of  the  muscular  fibres,  with  which,  in  many  parts,  this  mem- 
brane is  surrounded. 


OF  THE  MUCOUS  MEMBRANE.  199 

4.  Sensations,  more  or  less  distinct  or  obscure,  general  or 
special,  and  feelings  of  want,  or  of  appetites. 

§  277.  The  mucosities  or  the  mucous  humours  that  are 
found  on  the  surface  of  the  internal  tegument,  are  for  the 
most  part  composed  of  mucus.  Animal  mucus*  very  ana- 
logous to  vegetable  mucilage,  but  containing  nitrogen  in  addi- 
tion, is  one  of  the  immediate  principles  of  animals.  It  is 
found  both  internally,  in  the  product  of  the  mucous  secretion, 
and  externally  in  the  epidermis,  hairs  and  horny  parts,  of 
which  it  forms  a  considerable  portion.  In  a  pure  and  liquid 
state,  it  is  white,  viscid,  transparent,  inodorous,  and  insipid;  it 
contains  nine-tenths  of  its  weight  of  water;  it  is  insoluble  in 
alcohol,  soluble  in  acids,  not  coagulable  like  albumen,  and  not 
congelable  like  gelatine;  it  is  precipitated^  by  the  acetate  of 
lead;  in  a  dry  state  it  is  semi-transparent,  fragile,  insoluble 
in  water,  soluble  with  difficulty  in  acids. 

M.  Berzelius  has  proved  the  identity  of  the  mucus  of  the 
nose  and  trachea,  and  found  it  composed  as  follows:  water, 
933.9;  mucous  matter,  53.3;  hydrochlorate  of  potash  and 
soda,  5.6;  lactate  of  soda  and  animal  matter,  3.0;  soda,  0.9; 
phosphate  o£  soda,  albumen  and  animal  matter,  3.3. 

In  the  analysis  of  the  other  mucosities  given  by  this  savant, 
and  in  those  of  Messrs.  Fourcroy  and  Vauquelin,  there  are  con- 
siderable differences,  some  of  which  depend  on  the  difference 
of  parts  whence  the  mucosity  was  taken,  and  where  it  had 
been  mixed  with  various  matters,  and  others  on  the  difference 
of  the  individuals  affected  with  different  diseases.  In  fact, 
although  mucus  is  always  identical,  mucosity  is  neither  al- 
ways nor  everywhere  the  same;  generally  it  coagulates  milk. 

§  278.  The  functions  of  the  mucous  membrane  are  very 
closely  connected  with  those  of  the  other  parts.  In  a  healthy 
state,  the  nervous  action,  the  circulation,  the  functions  of  the 
skin,  &c.  have  a  manifest  influence  on  the  functions  of  the 
mucous  membrane,  and  vice  versa.  In  a  state  of  disease,  the 
mucous  membrane  produces  very  remarkable  sympathetic 
effects,  and  experiences  also  those  produced  by  other  parts. 

*  See.  Fourcroy  and  Vauquelin,  Annahs  du  Mus.  cThist.  nat.  vol.  xii. — 
Bostock,  Medico-Chir.  Transact,  vol.  iv. — Berzelius,  ibid  vol.  iii. 
27 


200  GENKKAL   ANATOMY. 

§  279.  The  origin  of  the  mucous  membrane,  from  the  very 
beginning  of  the  egg  and  its  development  in  the  embryo,  have 
been  already  pointed  out.  (256.)  "There  yet  remains  unde- 
scribed  the  formation  of  the  villosities;  it  is  to  M.  Fr.  Meckel 
that  we  are  indebted  for  our  knowledge  of  this  point  of  em- 
bryogeny.  The  villosities  are  formed  at  a  very  early  period. 
From  the  beginning  of  the  third  month,  they  are  visible  in  the 
form  of  closely-joined,  longitudinal  plaits.  These  plaits  after- 
wards present,  on  their  free  edge,  notches  like  the  teeth  of  a 
saw,  which  successively  augment  in  depth;  and  towards  the 
end  of  the  fourth  month,  the  plaits  are  replaced  by  that  multi- 
tude of  little  eminences  which  constitute  the  villosities.  They 
are  at  first  tolerably  large  and  very  distinct  till  the  seventh 
month.  In  the  commencement  they  are  as  numerous,  although 
shorter,  in  the  large  intestine,  as  in  the  small  one.  Those  of 
the  large  intestine  afterwards  diminish  in  number  till  birth. 
We  should  observe  that  in  reptiles,  these  villosities  are  re- 
placed by  little  longitudinal  folds. 

§  280.  The  differences  of  the  mucous  membrane,  as  regards 
the  sexes,  races,  and  individuals,  are  not  such  as  can  be  gene- 
rally described,  excepting  always  the  difference  of  conforma- 
tion in  the  genital  and  urinary  organs  of  the  two  sexes.  The 
mucous  membrane  of  the  digestive  canal,  is  thicker  in  the  hu- 
man species  than  in  the  mammiferous  carnivora,  but  thinner 
than  in  the  herbivora;  the  peritoneal  covering  of  the  intestine, 
on  the  contrary,  is  thinner  in  the  herbivora,  and  thicker  in  the 
carnivora  than  in  man. 

§  281.  The  teeth,  as  has  been  already  stated,  are  appendages 
of  the  mucous  membrane  of  the  mouth, -prolonged  into  the  al- 
veoli, as  far  as  the  papilla  or  dental  pulp,  appendages  which 
may  be  compared  to  the  hairy  appendages  and  horns  of  the 
external  skin. 

§  282.  The  mucous  membrane  is  subject  to  extremely  varied 
and  numerous  morbid  alterations:  it  participates  in  the  primi- 
tive and  acquired  vices  of  conformation,  of  the  organs  of  which 
it  is  a  part,  as  well  as  of  their  displacements.  It  alone  also 
undergoes  displacements,  more  or  less  extensive,  through  the 
loosened  texture  of  the  sub-mucous  tissue,  particularly  in  the 


OF  THE  MUCOUS  MEMBRANE.  201 

oesophagus,  intestine,  and  bladder,  constituting  a  false  diverti- 
culum.  The  mucous  membrane  also  presents  other  prolonga- 
tions, depending  on  its  elongation  and  the  laxity  of  the  sub- 
mucous  tissue;  such  are  certain  prolongations  of  the  plaits  or 
valvuli  conniventes,  of  the  uvula,  prolapsus  ani,  of  the  vagina, 
&c.  Particular  polypi,  also  appears  to  be  a  mere  vegetation, 
or  hypertrophy  of  the  membrane  and  sub-mucous  tissue;  but 
generally  there  is  an  accidental  tissue  produced.  Tumours  of 
the.  eye-lids,  of  the  amygdalae,  and  of  the  uvulae  vesicae,  should 
be  regarded  as  a  hypertrophy  of  this  membrane  and  its  folli- 
cles. 

§  283.  The  mucous  membrane  is  very  subject  to  a  serous 
and  mucous  discharge,  which  constitutes  the  phlegmorrhagies 
and  blennorrheae  without  inflammation.  The  sub-mucous  tis- 
sue itself,  although  rarely,  is  subject  to  an  oedema  or  serous 
infiltration.  This  membrane  is  frequently  the  seat  of  hemor- 
rhage or  bloody  discharges;  the  sub-mucous  tissue  is  also 
sometimes  in  a  state  of  ecchymosis.  It  is  also  certain  that  it  is 
the  seat  of  a  gaseous  evolution  or  secretion. 

§  2S4.  Inflammation  is  very  common  in  it,  under  all  its 
forms.  Its  anatomical  characters,  are  increased  redness,  some- 
times verging  to  a  brown;  a  degree  of  thickening,  generally 
slight,  but  variable,  and  proportioned  to  the  duration  of  the 
disease;  a  softening  more  or  less  marked;  and  sometimes  an 
enormous  augmentation  of  the  villosities.  The  most  usual  re- 
sult of  this  inflammation,  is  an  augmentation  of  the  quantity 
of  the  mucus,  and  of  a  change  in  its  qualities.  This  catarrhal 
inflammation  often  degenerates  intophlegmorrhea  or  blennor- 
rhea.  Suppurative  inflammation  also  frequently  occurs  in  it; 
the  membrane  without  being  ulcerated  secretes  mucus  and 
pus,  or  even  pure  pus  alone.  Abscesses  are  also  sometimes 
found  in  the  sub-mucous  cellular  tissue.  The  plastic  inflam- 
mation is  less  frequent.  It  is,  however,  frequently  observed 
in  the  trachea  and  bronchiss,  where  it  constitutes  croup,  and 
not  unfrequently  in  the  alimentary  canal,  the  intestines,  blad- 
der, urethra,  and  sometimes  even  in  the  eyes.  The  organ iza- 
ble  matter  is  usually  excreted  in  pieces,  or  membranes,  of  suf- 
ficient size  and  consistence  to  have  been  taken  for  the  internal 


202  GENERAL  ANATOMY. 

membrane  of  the  stomach,  or  of  the  bladder,  &c. ;  or  the  patient 
dies  before  its  organization;  at  other  times,  on  the  contrary,  the 
new  membrane  becomes  organized,  and  united  to  the  surface 
of  the  old  one,  or  it  contracts  adhesions  with  itself,  and  thus 
forms  mucous  bridles  in  greater  or  less  number,  which  tra- 
verse and  contract  more  or  less  the  cavity  they  occupy. 

The  inflammation  of  the  mucous  membrane  is  not  always 
erythematous,  and  uniformly  extended  over  its  surface;  it 
sometimes  assumes  the  form  of  red  isolated  patches,  and  often 
that  of  exanthematous  buttons,  whether  the  little  elevations  be 
separate  or  confluent.  It  is  known  that  this"  may  be  some- 
times, but  not  always,  seen  upon  the  mucous  membrane  of  the 
digestive  and  respiratory  canals,  of  individuals  who  have  died 
of  small-pox,  and  that  it  has  in  that  case  been  regarded  as  an 
internal  variola.*  This  internal  exanthema,  which  appears 
to  consist  in  an  inflammation  confined  to  the  follicles,  has  been 
particularly  observed  by  Mr.  Bretonneau  in  an  epidemic  en- 
teritis, whose  description,  it  is  to  be  regretted,  he  has  not  yet 
published. 

§286.  Gangrene,  sometimes, and  ulceration, frequently,  take 
place  in  the  mucous  membrane,  particularly  after  the  exan- 
thema of  which  we  have  been  speaking.  After  either  of  these 
causes  of  destruction  if  the  individual  survives,  a  new  mem- 
brane is  soon  formed  in  the  destroyed  places,  having  all  the 
characters  of  the  old  one.  We  have  already  said,  that  the 
membranes  of  abscesses,  those  of  chronic  abscesses  particular- 
ly, and  above  all  that  of  fistulas  in  the  neighbourhood  of  the 
anus,  as  well  as  that  of  the  fleshy  buds,  is  a  mucous  mem- 
brane, like  that  of  fistulas.  The  serous  and  synovial  mem- 
branes which  suppurate,  assume  the  same  character.  When,  on 
the  contrary,  a  mucous  cavity  becomes  the  seat  of  dropsy,  the 
membrane  assumes  the  aspect  of  the  serous  membranes:  this  is 
seen  to  happen  in  the  fallopian  tubes,  the  maxillary  sinuses, 
and  less  completely  in  the  gall  bladder,  and  the  duct  of  the 
sub-maxillary  gland.  Certain  cysts,  also,  by  their  texture  and 

*  See  Wrisberg.  in  sylloge  Comment,  p.  52, — G.  Blane  in  Transact,  for  the, 
improvement  of  med.  and  chirur.  knowL  vol.  iii.  p.  423 — 428. 


OF  THE   MUCOUS  MEMBRANE.  203 

humours,  belong  to  the  mucous  membrane:  such  in  particular 
are  the  atheroma;  but  as  will  be  seen  hereafter,  the  atheroma 
are  often  follicles  of  the  skin,  and  in  that  case  it  is  a  slight 
transformation  only. 

§  287.  The  mucous  membrane  is  subject  to  various  sorts  of 
accidental  productions,  either  healthy  or  morbid.  Sometimes 
the  natural  mucous  membrane  of  the  vagina,  during  a  prolapsus, 
that  of  the  prepuce  in  phymosis,  that  of  fistulas,  and  particu- 
larly in  the  lungs,  become  more  or  less  perfectly  cartilaginous, 
and  sometimes  even  bony,  either  by  transformation,  or  by  a 
new  production.  Serous  cysts  have  sometimes  been  observed 
both  in  its  thickness  and  beneath  it.  Accidental  hairs  are 
sometimes  found  on  the  surface  of  this  same  membrane.  Im- 
perfect horny  productions  are  likewise  found  in  it.  Although 
fatty  tumours  are  rare  in  the  sub-mucous  tissue,  they  have  been 
found  in  it:  erectile  productions  in  this  same  sub-mucous  tissue 
are  observable,  frequently  about  the  anus,  and  sometimes  in 
other  parts  of  the  intestinal  canal.  Finally,  morbid  produc- 
tions are  frequently  remarked  there. 

§  288.  The  cadaverous  changes  of  the  mucous  membrane, 
have  been  already  partly  indicated  274.  This  membrane,  soon 
after  death,  becomes  coloured  by  the  infiltration  of  the  hu- 
mours that  cover  it.  Thus  in  the  intestine  opposite  the  nates, 
it  is  yellowish;  it  presents  livid  marks,  corresponding  to  the 
larger  sub-mucous  veins,  and  becomes  greenish  in  the  gall 
bladder,  &c. 

In  certain  kinds  of  death,  and  in  some  internal  parts,  it  is  the 
seat  of  sanguineous,  or  sero-sanguineous  congestions.  In  death 
from  apoplexy,  hydrothorax,  and  particularly  from  strangula- 
tion, in  a  word,  in  all  those  cases  where  there  is  a  difficulty  of 
breathing  previous  to  death,  it  frequently  happens  that  the 
congestion,  after  having  been  at  first  confined  to  the  sub-mu- 
cous veins,  and  then  to  the  vessels  of  the  membrane  itself, 
finally  proceeds  to  hemorrhage  in  the  stomach  and  intestines, 
as  Boerhaave  and  Morgagni  had  already  stated,  as  M.  Yelloly 
has  observed,*  and  as  I  myself  have  several  times  seen,  after 

*  MedicO'chirurg.  Transact,  vol.  iv  p.  371. 


204  GENERAL   ANATOMY. 

this  kind  of  death,  both  in  men  and  animals  This  congestion 
is  easily  distinguished  from  inflammation  by  the  absence  of  all 
morbid,  mucous,  purulent  or  plastic  product  on  the  surface  of 
the  membrane,  by  the  other  cadaverous  phenomena  depending 
on  the  settling  of  the  blood  in  the  right  side  of  the  heart,  and 
especially  by  the  state  of  the  skin,  which,  like  the  mucous 
membrane,  presents  livid  spots  and  sometimes  echymoses. 


SECTION  III. 

OF  THE  SKIN. 

§289.  The  skin,  pellis,  cutis,  corium^  6tp,ua,  constitutes  the 
external  tegument;  it  is  a  compound  membrane  furnished  with 
various  appendages,  which  envelops  and  protects  the  body, 
and  has  other  important  functions. 

§  290.  Galen  has  made  some  remarks  upon  the  structure  of 
the  skin,  and  particularly  upon  its  functions.  The  anonymous 
author  of  the  Anatomical  Introduction,  and  after  him,  Avicenna, 
were  the  first  who  spoke  of  the  fleshy  panicle,  panniculus  carno- 
sus.  Vesalius  and  Columbus  still  thought  the  skin  was  perforat- 
ed by  the  natural  openings:  but  Casserius,  as  we  have  already 
seen,  had  observed  that  it  was  continued  into  the  nostrils  and 
mouth;  we  are  also  indebted  to  him  for  a  figure  of  the  epider- 
mis, separated  from  the  dermis.  J.  Fabricius  has  given  a  very 
exact  and  detailed  account  of  the  various  appendages  of  the 
skin  of  animals;  since  then,  the  observations  of  anatomists 
upon  this  organ,  have  been  greatly  increased.* 

*  M.  Malpig'hi,  de  lingua  extrc.it.  epist. — dc  Externo  tactu  organo  epist.,  iti 
op.omn.  torn  ii. — J..M.  Hoffmann,  de.  cuticula  et  cute.  Altd.  1685. — Littre, 
Obs.  sur  les  differentes  parties  de  la  peau,  etc.  Acad.  roy.  des  Sci.  1702. —<• 
F.  de  Riet,  de  Organo  tactts.  Lug-d-Bat.  1743. — J  Fantoni,  de  Carports  inte- 
gumentis,  etc.  Turin,  1746. — Lecat.  Traite  des  sens. — Cruikshank,  Experi- 
ments on  the  insensible  perspiration,  etc.  Loud.  1795. — C.  F.  Wolff,  de  Cute, 
in  nov.  Com.  Petrop.  vol.  viii. — G.  A.  Gautier,  Rechcrches  sur  forgane  cutanc. 
Paris,  1811. — Dutrochet  Obs.  sur  la  struct,  dc  la  pcau.  Journ.  compl. 
vol.  v. — J.  F.  Schroter,  das  Memchlich  Geftihl,  dc.  Leipzig,  1814. — Law- 
rence in  Rees*  Cyclopaedia.— Seller  in  Anat.  phys'wl.  RealworterbbcH- 


UF  THE  SKIN    IN  UKNKKAL.  205 

ARTICLE  I. 
OF  THE   SKIN  IN  GENERAL. 

§291.  This  membrane,  extended  over  the  whole  surface  of 
the  body,  whose  figure  in  many  of  the  inferior  animals  it  deter- 
mines, and  receiving  on  the  contrary  the  form  of  man  and  the 
other  vertebrata,  is  in  fact  moulded  on  the  subjacent  organs, 
permitting  their  more  strongly  marked  projections  to  be  seen. 
Everywhere  continuous  to  itself,  an  apparent  interruption  is 
only  to  be  found  in  various  places  on  the  median  line,  called 
the  raphe,  and  which  indicates  it  to  have  consisted  originally 
of  two  separate  halves.  This  raphe  is  well  marked  in  those 
places  where  the  two  halves  unite  last,  and  where  anormal 
divisions  are  most  usually  found,  as  in  the  upper  lip,  in  the 
perineum  and  below  the  umbilicus.  The  skin  seems  perfo- 
rated, but  is  not,  at  the  apertures  of  the  digestive  canal,  and 
the  orifices  of  the  respiratory,  urinary  and  genital  organs, 
places  where  it  is  reflected  and  continues  on,  changing  its 
character  with  the  internal  skin.  It  is  the  same  at  the  rneatus 
auditorius  externus,  where  it  sends  a  cutaneous  prolongation 
to  the  eyes  and  the  ducts  of  the  mamma?,  into  which  it  trans- 
mits others  of  a  mucous  nature. 

§  292.  The  skin  presents  two  surfaces.  The  free  surface, 
which  is  external  and  in  contact  with  the  atmosphere,  pre- 
sents various  objects  for  consideration:  we  there  see  wrinkles 
or  folds  more  or  less  deep,  some  of  which  depend  on  the  sub- 
cutaneous muscles  situated  on  the  he.ad,  neck,  and  about  the 
anus,  where  the  skin  can  not  accompany  their  contraction;  it 
is  the  same  with  respect  to  the  wrinkles  on  the  scrotum  occa- 
sioned by  the  contraction  of  the  subjacent  tissue;  others  an- 
swer to  the  articulations  and  are  caused  by  their  motions: 
such  are  those  of  the  hands,  feet,  &c. ;  others  again  depend 
upon  emaciation  and  muscular  atrophy,  when  these  phenome- 
na are  rapidly  produced  and  at  a  sufficiently  advanced  period 
of  life  for  the  skin  to  have  lost  its  contractility.  The  surface 
of  the  skin  presents,  besides,  small  wrinkles,  in  the  palm  of 
the  hand  and  sole  of  the  foot,  that  are  peculiar  to  the  epider- 


206  GENERAL  ANATOMY. 

mis;  they  are  salient  lines  separated  by  depressed  ones,  various- 
ly directly  and  formed,  and  which  are  made  by  series  of  pa- 
pillae On  the  back  of  the  hand,  and  on  the  forehead  they  are 
polygons;  on  the  cheeks  and  breast,  mere  points  and  rudiments 
of  stars,  &c.  We  also  find  on  the  free  surface  of  the  skin, 
small  round  openings  that  are  every  where  distributed,  and 
particularly  abundant  in  the  face:  they  are  the  orifices  of  the 
sebaceous  follicles.  There  are  others  still  smaller,  microsco- 
pic openings  or  apparent  pores  of  the  epidermis,  but  in 
reality,  infundibuliform  depressions,  terminating  in  a  cul-de- 
sac.  This  surface  is  in  general  tolerably  smooth;  it  is  slight- 
ly moistened  by  the  transpiratory  fluid  and  the  sebaceous 
matter. 

§  293.  The  deep  or  adhering  surface  of  the  skin  is  con- 
nected, in  general,  with  the  subjacent  parts  by  loose  cellular 
tissue,  which  permits  a  mutual  sliding  between  the  skin  and 
the  parts  it  invests.  Sub-cutaneous  bursae  mucosse,  in  some 
places,  interrupt  the  continuity  of  the  cellular  tissue,  and 
greatly  increase  the  motility  of  the  skin  and  parts  beneath. 
In  other  places,  on  the  contrary,  the  cellular  tissue  is  dense, 
firm  and  scarcely  distinguishable  from  the  skin:  it  is  soon 
the  head,  back  of  the  neck,  back,  and  abdomen.  In  others 
again,  it  is  by  fibrous  or  ligamentous  tissue  that  the  skin  ad- 
heres to  parts  beneath;  this  is  the  case  at  the  wrist,  instep, 
palm  of  the  hands,  sole  of  the  foot,  and  particularly  under  the 
heel.  Adhesion  is  effected  in  some  places  by  means  of  a 
reddish,  cellular,  semi-muscular  tissue,  if  I  may  be  allowed 
so  to  call  it;  such  is  the  dartos  in  the  scrotum  and  the  labia  pu- 
dendi.  Finally,  in  some  places  it  is  the  muscles  that  line 
the  skin  attached  to  them;  such  are  the  sub-cutaneous  mus- 
cles of  the  cranium,  of  the  face,  of  the  neck  and  of  the  hand. 
The  fleshy  panicle  of  the  mammiferous  animals,  more  high- 
ly developed  than  that  of  man,  in  the  face  excepted,  is  analo- 
gous to  the  sub-cutaneous  muscles  of  the  latter.  .  The  anato- 
mists of  the  middle  ages  have  strongly  doubted  or  denied  its 
existence  in  man;  that  it  does  exist,  is  evident,  but  its  extent 
is  but  small.  In  many  places  the  sub-cutaneous  cellular  tissue 
is  mixed  with  adipose  tissue,  and  these  two  penetrate  into  the 


OF  THE  SKIN  IN  GENERAL.  207 

thickness  of  the  skin  together.  The  sub-cutaneous  cellular 
tissue  is  traversed  by  large  veins,  by  numerous  arteries,  lym- 
phatics and  nerves. 

§  294.  The  cutaneous  or  sebaceous  follicles*  bear  the  strong- 
est resemblance  to  the  mucous  follicles. 

They  exist  throughout  the  whole  extent  of  the  skin,  at  least 
it  is  so  admitted,  the  palm  of  the  hand  and  sole  of  the  foot 
excepted.  Their  existence  is  conceded,  because  the  whole 
surface  of  the  skin  is  covered  with  the  sebaceous  humour;* 
because  by  careful  dissection,  aided  by  a  lens,  they  are  dis- 
covered in  places  where  they  are  excessively  slender;  and 
because  certain  morbid  changes  render  them  evident  in  places 
where  they  are  not  otherwise  perceptible.  They  are  particu- 
larly abundant  where  there  are  hairs,  in  the  vicinity  of  orifices 
and  in  the  folds  of  the  groin  and  axilla.  They  are  placed  in 
the  thickness  of  the  skin  or  beneath  it;  an  excellent  view  of 
them  may  be  attained  by  cutting  through  the  skin  obliquely. 
Their  orifices  form  tolerably  distinct  pores  on  the  surface. 
They  are  about  the  size  of  a  grain  of  millet,  or  even  smaller; 
they  vary  in  size;  those  of  the  nose  are  tolerably  large,  in  the 
cheeks  they  are  much  smaller.  Their  figure  is  that  of  a  little 
ampulla.  They  are  generally  simple  and  separate;  those  of 
the  nose,  however,  are  very  closely  approximated;  some  of 
them  are  confluent,  or  compound.  They  consist  in  a  little 
ampulla  formed  by  the  skin,  thinned,  reflected,  and  furnished 
with  numerous  vascular  ramusculi.  They  contain  an  oleo-al- 
buminous  matter  that  differs  a  little  in  the  various  regions  of 
the  body. 

§  295.  The  anatomical  texture  and  composition  of  the  skin, 
are  delicate  points  of  anatomy,  that  have  greatly  exercised  the 
patience  of  observers,  and  upon  which  they  are  far  from  agree- 
ing. From  a  very  early  period,  it  was  seen,  that  the  skin 
was  composed  of  two  layers,  one  thick  and  deep,  the  other 
thin  and  superficial.  Malpighi  perceiving,  that  in  a  bullock's 
tongue,  the  papilla  of  the  derm  is  are  separated  from  the  epi- 


*  J.  Ch.  Th.  Reusse,  prseside  Autenrieth,  de  Glandulis  sebacefs  dissert,  etc, 
Tubingoe,  1807. 

28 


208  GENERAL  ANATOMY. 

dermis  by  a  mucous  or  glutinous  layer,  which  fills  up  the  in- 
tervals like  a  net-work,  transferred  that  layer,  by  analogy,  to 
the  skin  of  man;  Ruysch  afterwards  gave  a  figure  of  this  net- 
work. From  that  period  anatomists  have  been  singularly  di- 
vided as  to  the  existence  of  this  membrane:  some  denying  it 
entirely,  and  admitting  only  the  dermis  and  epidermis  as  con- 
stituents of  the  skin;  others  admitting  its  existence  in  the  co- 
loured race  only;  others  again  improving  upon  Malpighi,  and 
admitting  of  several  layers  in  the  mucous  body  of  the  skin,  as 
many,  as  it  were,  as  there  are  anatomical  elements  in  that 
membrane,  or  as  it  exercises  functions. 

§  296.  The  blood-vessels,  lymphatics,  and  nerves  of  the 
skin  penetrate,  as  they  divide,  through  the  areola  of  the  der- 
mis: supported  by  a  fine  cellular  tissue  which  surrounds  them, 
they  thus  attain  its  superficies,  where  they  are  increased  to 
myriads,  which  by  their  ultimate  divisions  constitute  the  pa- 
pillae and  the  vascular  net- work.  As  relates  to  the  disposition 
of  these  parts,  and  particularly  of  the  vessels,  it  has  been  gene- 
rally conceded  that  they  are  foreign  to  the  dermis,  and  that 
they  merely  traverse  it  to  form  the  vascular  net-work  above. 
M.  Chaussier,  on  the  contrary,  admits  that  all  the  anatomical 
elements  of  the  skin  are  united  in  the  dermis  itself.  Gordon 
even  goes  so  far  as  to  say  that  the  injected  dermis  is  every 
where  equally  vascular,  as  much  so  on  its  deep  surface  as  on 
its  superficies.  To  say  that  the  vessels  are  foreign  to  the  der- 
mis, and  that  they  merely  form  a  sub-jacent  layer  to  it,  would 
be  incorrect;  but  it  would  be  equally  so  to  affirm,  that  the  ves- 
sels are  as  much  divided,  and  are  as  numerous  on  the  deep  face 
of  the  dermis,  as  they  are  on  its  opposite  one.  The  vessels 
divide  and  ramify  in  the  dermis,  as  they  penetrate  into  its 
thickness,  and  their  last  divisions, prodigiously  multiplied,  are 
distributed  in  the  external  surface  of  that  membrane,  and  in 
the  eminences  that  cover  it,  parts,  consequently,  much  more 
vascular  than  the  deep  face.  It  is  precisely  the  same  as  re- 
gards the  nerves. 

§  297.  The  dermis  or  corium,  corium,  derma,  vera  cutis, 
is  a  fibro-cellular  membrane,  which  constitutes  the  deep  and 
principal  layer,  and  almost  all  the  thickness  of  the  skin.  Its 


OF  THE  SKIN  IN  GENERAL.  209 

internal  face,  which  is  that  of  the  skin,  presents,  in  general, 
conical  alveolar  openings,  directed  ohliquely  into  the  thickness 
of  the  membrane.  These  areolae,  which  are  very  large  in  the 
dermis  of  the  hand,  of  the  sole  of  the  foot,  of  the  back,  of  the 
abdomen,  of  the  limbs;  narrower  in  the  neck,  breast,  and  face 
particularly,  are  nearly  invisible  in  the  back  of  the  hand  and 
foot,  forehead,  scrotum  and  labia  pudendi.  The  edges  of  these 
areolae  are  continued,  the  first  and  largest  along  with  the  sub- 
cutaneous fibrous  tissue;  the  second  with  the  more  or  less  dense 
cellular  tissue;  the  last  or  narrowest,  with  the  very  loose  tissue 
that  is  found  in  the  regions  where  they  are  observed;  the  areola 
themselves  are  filled  with  an  adipose  cellular  tissue,  and  are 
traversed  by  the  nerves  and  vessels  of  the  skin.  The  bottom 
of  these  alveolar  cavities  is  perforated  by  very  small  holes, 
which  correspond  to  the  superficial  face  of  the  dermis.  This 
face  tolerably  smooth,  in  general,  presents,  in  various  places, 
little  papillary  eminences,  that  are  much  more  apparent  on  the 
denuded  dermis,  than  when  seen  through  the  epidermis. 

§  298.  The  papillary  body,  and  the  vascular  net-work  of  the 
skin,  which  have  been  unhappily  described  as  being  distinct 
layers  of  this  membrane,  belong  to  the  superficial  face  of  the 
dermis.  The  papillae*  discovered  by  Malpighi,  and  since  ac- 
knowledged, figured,  and  described  by  Ruysch,  Albinus,  and 
many  other  anatomists;  lately  described  by  Gautier,  under  the 
name  of  buds:  and  doubted  by  Cheselden  and  others,  are  very 
diminutive  projections  or  eminences,  generally  conoid  on  the 
surface  of  the  dermis ;  perfectly  visible  on  the  tongue,  ar- 
ranged in  double  lines,  and  very  distinct  in  the  palms  of  the 
hands,  soles  of  the  feet,  and  pulp  of  the  fingers;  still  distinct, 
but  irregularly  distributed  in  the  nipple  and  lips;  but  so  ex- 
tremely small  and  undistinguishable  in  the  rest  of  the  skin,  that 
they  have  been  admitted  to  exist  there  more  from  analogy, 
than  from  actual  observation,  and  that  they  are  confounded  in 
the  surface  of  the  dermis  in  a  vascular  and  nervous  net-work. 
These  papillae,  in  those  places  where  they  are  very  distinct, 

*  Hintze,  de  papillis  cutis  tadui  inservientibus.  L.  B.  1747 — Albinus.  JLcad. 
annot,  lib.  iii.  cap,  ix.  et  xii. 


210  GENERAL  ANATOMY. 

evidently  consist  of  a  very  soft,  very  cellular  projection  of  the 
clermis,  penetrated  by  numerous  nervous  threads,  deprived  of 
the  neurilema,  and  of  vascular  ramusculi,  and  having  an  erec- 
tile disposition  which  will  be  described  hereafter  (chap.  iv). 
In  those  places  where  the  papillae  are  less  distinct,  although 
the  texture  and  composition  of  the  dermis  are  essentially  the 
same,  there  are  fewer  nerves ;  the  vessels,  which  are  very 
abundant,  form  a  net-work.  The  blood  penetrates  constantly, 
but  in  variable  quantities  into  the  vessels  of  the  dermis.  In 
echymosis  of  the  skin  it  goes  still  further,  and  passes  into  the 
mucous  body.  Fine  and  penetrating  injections,  after  filling 
the  papillary  and  vascular  body  of  the  skin,  sometimes  spread 
beyond  it* 

§  299.  The  texture  of  the  dermis  is  that  of  an  areolar  web 
more  or  less  close:  the  fibre  that  forms  it  is  peculiar  to  it.  It 
was  considered  by  the  older  anatomists  as  intermediate  to  the 
muscular  fibre,  and  the  aponeurotic  tissue.  Some  have  stated 
it  to  be  altogether  cellular,  others  ligamentous.  Even  quite 
recently,  M.  Osiandert  has  maintained  that  it  is  distinctly  mus- 
cular on  the  internal  face  of  the  skin.  His  observations  were 
made  on  the  skin  of  the  abdomen  in  women  who  died  in  par- 
turition. The  tissues  to  which  it  bears  the  greatest  resem- 
blance by  the  ensemble  of  its  characters,  are,  the  cellular  and 
fibrous  tissues. 

§  300.  The  dermis  is  white:  its  external  surface  is  more  or 
less  reddish,  according  to  the  greater  or  less  quantity  of  blood, 
remaining  in  its  small  vessels.  Its  thickness  is  not  every 
where  the  same,  varying  from  one  line  and  a  half,  to  a  fourth 
of  a  line.  In  the  trunk  it  is  generally  greater  behind  than  be- 
fore ;  in  the  limbs  more  so  externally,  than  internally.  The 
dermis  is  particularly  very  thin  in  the  eye-lids,  mammae,  and 
the  organs  of  copulation;  very  thick,  on  the  contrary,  in  the 
palm  of  the  hands,  and  above  all,  in  the  sole  of  the  foot.  It  has 
a  semi-transparency  which  renders  the  colour  of  the  sub-cu- 
taneous veins  visible  through  the  skin.  It  has  a  power  of  re- 

*  See  Frochaska,  disquisitio  anat,  phyn.  or%anismi  &c.  Vienna:,  1812.  4°, 
f  Commentationcs  gottingcnses  recentiores.  Vol.  iv.  1820. 


OF  THE  SKIN  IN  GENERAL.  211 

sistance  or  cohesion,  which  renders  it,  in  the  mechanical  arts, 
fit  for  strong  bands.  It  is  submitted  in  the  arts  of  the  tanner, 
currier,  &e.  to  various  processes  which  prevent  its  putrefac- 
tion, and  increase  its  density  or  flexibility,  &c.  It  contains, 
naturally,  a  great  quantity  of  moisture,  whose  abstraction  ren- 
ders it  yellow  and  elastic.  Decoction  reduces  it  into  glue  or 
gelatine.  Besides  its  extensibility  and  retractility,  which  are 
very  great  and  which  continue  after  death,  it  possesses,  during 
life,  a  very  evident  tonic  power  of  contraction,  although  in  a 
much  smaller  degree  than  the  muscles.  It  is  this  contraction 
which  produces  what  is  commonly  called  goose-flesh.  It  is 
its  external  surface  that  is  the  seat  of  the  sense  of  touch.  The 
dermis1  is  the  support  of  all  the  rest  of  the  skin;  the  corpus 
mucosum  is  placed  on  its  surface. 

§  301.  The  corpus  mucosum,  of  Malpighi,*  reticulare  cor- 
pus^ rete  glutinosum  malpighianum^  is  a  very  thin  layer,  of 
a  semi-liquid  cellular  tissue,  which  clothes  the  papillary  surface 
of  the  dermis,  separates  it  from  the  epidermis,  adheres  closely 
to  each  of  them,  and  is  the  seat  of  colouring  matter.  This  part 
of  the  skin,  indicated  by  Malpighi,  well  observed  by  Meckel 
and  Albinus, acknowledged  by  most  anatomists,  at  least  in  the 
negro,  denied,  however,  by  some  of  them,  particularly  by  Bi- 
chat,  M.  Chaussier,  Gordon,  and  M.  Rudolphi,  can  not,  it  is 
true,  be  isolated  by  dissection,  but  may  be  seen  in  various  cir- 
cumstances. Whenever,  either  in  life  or  death,  the  epidermis 
is  separated  from  the  dermis,  we  can  perceive  on  one  or  the 
other,  and  sometimes  on  each  of  these  membranes  a  mucous 
layer,  which  covers  the  papillary  eminences,  and  fills  up  the 
spaces  between  them.  This  intermediate  membrane,  is  par- 
ticularly visible  in  the  negro,  very  visible  also  in  the  black 
spots  of  the  white  man,  and  even  very  distinct  on  a  piece  of 
white  skin,  in  the  collection  of  Hunter.  This  layer,  extremely 
thin  on  the  summits  of  the  papillae,  and  less  so  in  the  inter- 
vals, has  the  appearance  of  a  net-work,  but  is  not  perforated. 

*  See  Mecke],  Rechcrches  anatonu'gues  sur  la  nature  de  Fcpidcrme  et  du 
reseau  qu'on  appclle  malphigien,  Mem.  de  Pacad..  roy.  des  sc.  de  Berlin,  ann. 
1753. — Albinus,  Acadcm.  annot.  lib.  i.  cap.  i. — v. 


212  GENERAL  ANATOMY. 

Those  who  admit  of  only  two  membranes  in  the  skin,  consi- 
der it  as  the  deep  part  of  the  epidermis.  This  mucous  body,  of 
the  nature  of  which  it  is  difficult  to  form  an  exact  idea,  appears 
to  consist  of  a  plastic  liquid  or  a  semi-organized  cellular  tissue. 
Neither  the  blood,  nor  injections  show  any  vessels  in  it; 
liquids  penetrate  into  it,  however,  but  they  seem  to  be  im- 
bibed by  it,  or  to  be  contained  in  peculiar  interstices.  Nerves 
are  unknown  in  it,  and  it  is  by  a  pure  allegation  that  Mr.  Gall 
assimilates  it  to  the  grayish  substance  of  the  brain.  This 
membrane  forms  a  humid  varnish  which  covers  the  papillary 
and  vascular  surface  of  the  dermis.  Substances  which  enter 
into,  or  depart  from  the  economy  by  the  skin,  traverse  it,  it 
is  the  seat  of  colour,  and  that  of  the  horny,  scaly,  &c.  produc- 
tions, that  exist  naturally  in  the  skin  of  animals,  and  in  some 
part  of  that  of  man,  as  well  as  of  those  that  are  accidentally 
developed  there.  This  membrane,  which  is  so  thin,  and  whose 
existence  has  even  appeared  dubious,  seems,  in  some  animals, 
and  even  in  man,  at  least  in  some  parts  of  the  body,  and  in  cer- 
tain cases,  to  be  found  of  several  superincumbent  layers. 

§  302.  An  anonymous  author  had  already  pointed  out  this 
arrangement.  Cruikshank  observed  it  in  a  negro  dead  of 
small-pox;  Bay  ham  on  the  injected  skin  of  a  white  man,  in 
another  case  of  disease ;  Gautier,  by  various  processes,  has  de- 
monstrated it  on  the  skin  of  the  negro,  and  M.  Dutrochet  on 
the  skin  of  animals.  This  is  a  sufficient  number  of  observa- 
tions, to  demand  an  examination  before  we  reject  them:  1st,  on 
the  papillary  surface  of  the  dermis,  there  is  a  very  thin,  co- 
lourless, transparent  layer,  particularly  distinguishable  under 
the  scales  and  the  coloured  horns  of  animals,  in  the  negro  and 
even  in  the  white  man,  but  under  the  nails  only;  2d,  a  co- 
loured layer  very  distinct  in  negroes,  in  whites  marked  with 
coloured  ephelides,  and  much  less  so  where  the  skin  is  white; 
it  is  often  united  to  the  following;  3d,  a  superficial  colourless 
layer,  more  or  less  soft  or  encrusted  with  a  horny  or  calcarious 
substance;  it  is  distinct  in  several  animals,  slightly  in  the 
negro,  not  at  all  in  the  white  man,  except  in  the  nails,  hairs 
and  accidental  horny  productions.  This  layer  is  directly  co- 
vered by  the  epidermis. 


OF  THE  SKIN  IN  GENERAL. 

§  303.  The  pigment  of  the  skin1'  is  chiefly  seated  in  the 
corpus  mucosum  and  particularly  in  its  middle  layer,  but  the 
external  surface  of  the  dermis  and  the  internal  one  of  the  epi- 
dermis, also  partly  partake  of  it.  Anatomists  prior  to  Mal- 
pighi,  arid  some  even  since,  place  its  seat  in  these  two  mem- 
branes, particularly  in  the  latter.  The  colouring  matter  exists 
in  men  of  every  race,  albinos  excepted.  It  is  only  in  the 
negro,  however,  that  it  can  be  distinguished,  clearly,  from 
the  rest  of  the  skin.  Malpighi  had  only  announced,  that  the 
colour  of  the  skin  had  its  seat  in  the  rete  mucosum;  Littre  had 
tried,  but  in  vain,  to  obtain  the  colouring  matter,  separately, 
by  submitting  the  negro  skin  to  maceration,  in  order  to  swell 
the  mucous  body,  and  thus  to  separate  the  epidermis  from  the 
dermis.  Although  the  corpus  mucosum  is  soft  and  liquefia- 
ble,  we  can  succeed  in  separating  from  the  skin  of  the  negro 
scrotum  considerable  portions  of  the  coloured  mucous  body 
in  the  form  of  a  continuous  independent  membrane,  separate 
from  the  epidermis.  Most  generally,  however,  and  I  have 
often  tried  the  experiment,  the  maceration  separates  from  the 
dermis,  which  remains  but  very  slightly  coloured,  the  epider- 
mis and  corpus  mucosum  united  and  coloured;  it  is  only  with 
great  difficulty,  that  we  can  afterwards  separate  the  mucous 
body  in  the  form  of  a  membrane.  If  the  maceration  be  con- 
tinued in  a  small  quantity  of  water,  and  the  experiment  be 
made  on  the  skin  of  the  scrotum,  a  deeply  coloured  part,  the 
mucous  body  in  resolving  itself  into  a  sort  of  mucosity,  tinges 
the  water  and  finally  deposits  at  the  bottom  of  the  vase,  an 
impalpable  brown  powder.  Gautier  has  assigned,  as  the  spe- 
cial seat  of  the  colouring  matter,  the  middle  layer  of  the  corpus 
mucosum,  which  he  describes  under  the  name  of  gem?nules, 
as  an  undulated  layer,  which,  with  a  single  one  of  its  turns, 
would  cover  each  one  of  the  double  furrowed  lines  of  the  der- 
mis, of  the  palm  of  the  hand,  and  the  sole  of  the  foot.  It 

*  B.  S.  Albinus.  De  sede  et  causa  coloris  cefhiopum  etc.  homin,  etc. 
LugtL-Bat.  1737,  et  Annot.  lib.  i.  cap.  ii.  Meckel,  loc.  cit. — S.  T.  Scem- 
mering1,  Uelter  die  korperliche  vcrschie.denheit  des  negers  vom  europaer. 


214  GENERAL  ANATOMY. 

would  rather  appear,  that  the  pigment  results  from  coloured 
globules,  disseminated  through  the  corpus  mucosum. 

The  mucous  body  is  not  only  more  coloured,  it  is  also 
thicker  in  the  negro,  than  in  other  races,  and  its  thickness  in 
the  latter  is  in  direct  proportion  to  its  colour;  thus,  it  is  so 
extremely  thin  in  the  white  man,  that  its  very  existence  has 
been  doubted.  It  is  still  thinner  and  so  liquid  in  albinos,  that 
the  action  of  the  sun  easily  vesicates  their  skins,  while  in  the 
negro  it  is  with  difficulty  that  epispastics  produce  that  effect. 

The  colouring  matter  of  the  skin  is  very  analogous  to  that 
of  the  blood;  it  appears  to  be  secreted  from  that  humour  and 
to  pass  from  the  vessels  of  the  surface  of  the  dermis  into  the 
mucous  body,  where  it  is  in  a  kind  of  imbibition.  Various  mor- 
bid phenomena  induce  a  belief  that  it  is  continually  renewed 
there,  by  an  unceasing  deposition  and  absorption.  Beddoes 
and  Fourcroy  have  observed  by  experiment,  that  the  negro 
skin  plunged  into  water,  impregnated  with  the  vapour  of 
chlorine,  becomes  white,  and  in  a  few  days  resumes  its  black 
colour  in  all  its  intensity.  The  chemical  observations  of  Davy, 
Coli  and  others  have  demonstrated  that,  which  Blumenbach 
had  long  before  asserted,  viz:  that  the  pigment  of  the  skin  is 
chiefly  formed  of  carbon. 

The  use  of  the  pigment  in  the  coloured  races,  appears  to  be, 
to  defend  the  skin  against  the  rubefacient  effect  of  the  rays  of 
the  sun,  commonly  called  a  coup  de  soleil.* 

§  304.  The  epidermis  or  cuticle,  epidermis,  cuticiilaj  is  a 
distinct,  though  thin  layer  of  the  skin,  which  forms  a  kind  of 
dry  and  defensive  varnish  on  its  surface.  The  free  or  super- 
ficial surface  of  this  membrane,  which  is  also  that  of  the  skin, 

*  See  Philosoph.  Transact,  ann.  1821,  I.  On  the  black  rete  mucosum,  &c. 
by  Sir  Ed.  Home. 

f  H.  Fabricio,  de  totius  animalis  integumentis,  ac  primo  de  cuticula,  et  Vs 
quae  supra  cuticulam  sunt,  in  oper  omn. — Ludwig  de  cuticuld.  Lipsiz,  1739. 
— Meckel,  he.  cit  et  Nouvelles  observations  sur  les  rtpiderme.  Mem.  de  1'acad. 
roy.  des  sc.  de  Berlin,  ann.  1757. — Monro,  sen.  de  cuticuld  humana,  oratio, 
in  works.  Edinb.  1781. — J.  Th.  Klinkosch  et  Hermann,  de  vera  naturae  cu- 
ticula  ejusque  regeneratime.  Prag-ac,  1775. — B.  Mojon,  Sulf  epidermide,  etc, 
Genao,  1815. 


OF  THE  SKIN  IN  GENERAL. 

presents,  as  \ve  have  already  seen  [292],  little  wrinkles  and 
eminences  variously  arranged,  and  very  visible  to  the  naked 
eye.  Moreover,  if  we  examine  this  surface  with  a  magnify- 
ing instrument,  and  even  with  a  simple  lens,  the  parts  of  the 
epidermis  between  the  little  wrinkles,  and  which  to  the.naked 
eye  seem  united,  then  appears  very  unequal,  rugous,  and  pre- 
sent little  depressions,  which  bear  the  greater  resemblance  to 
pores,  because  we  see  the  sweat  oozing  from  them. 

The  deep  face  of  the  epidermis  is  adherent,  and  can  not  be 
separated  from  the  rest  of  the  skin  by  dissection,  but  putre- 
faction, maceration,  the  action  of  dry  and  humid  heat,  epis- 
pastics,  and  various  diseases,  produce  this  separation.  When 
it  is  caused  by  incipient  putrefaction,  a  process  preferable  to 
all  others,  by  cautiously  raising  the  epidermis,  we  perceive  a 
multitude  of  very  fine,  transparent,  colourless  filaments,  which 
break  after  being  extended  to  a  certain  degree.  These  fila- 
ments, well  described  and  represented  by  W.  Hunter,  who 
considered  them  as  the  vessels  of  the  sweat,  had  been  previ- 
ously noticed  by  Kaau,  who  was  of  a  similar  opinion.  Bichat 
and  M.  Chaussier,  also,  believed  them  to  be  exhalent  and 
absorbing  vessels.  But  we  have  not  yet  been  able  to  inject 
them,  and  inflammation,  which  renders  the  skin  so  vascular, 
does  not,  sensibly,  colour  them.  Cruikshank,  on  the  other 
hand,  thinks  they  are  not  vessels,  but  excessively  fine  pro- 
longations of  the  epidermis,  which  line  the  smallest  pores  of 
the  dermis.  Seiler  seems  to  adopt  this  hypothesis,  and  accord- 
ing to  him,  they  are  rudiments  of  sebaceous  follicles  and 
bulbs  of  hairs.  It  is  not  certain,  however,  that  these  pro- 
longations exist  when  the  epidermis  adheres  to  the  dermis, 
and  we  may  consider  them  as  mucous  threads  formed  by  the 
intermediate  substance  of  the  dermis,  and  epidermis  rendered 
fluid  and  viscid  by  incipient  decomposition. 

The  epidermis  penetrates,  as  it  becomes  attenuated,  into 
the  sebaceous  follicles.  It  penetrates,  in  like  manner,  into  the 
openings  of  the  bulbs  of  the  hairs. 

§  305.  It  has  been  said  that  the  epidermis  was  composed  of 
imbricated  scales;  but  this  is  a  deceitful  appearance,  it  is  a  flat 

and  continuous  membrane.     Nunberger  admits  that  it  is  fur- 
29 


216  GENERAL  ANATOMY. 

nished  with  vessels,  and  that  it  is  nourished  by  intus-suseep- 
tion.  Mojon,  like  Klinkosch,  supposes  it  to  contain  fibres, 
lamina,  vessels,  and  all  the  properties  of  organization,  and  of 
life.  Mascagni  considers  it  as  being  entirely  formed  of  ab- 
sorbent vessels.  Fontana  had  previously  thought  he  saw  spiral 
vessels  in  it,  but  M.  de  Humboldt  found  these  supposed  ves- 
sels were  nothing  more  than  folds.  The  most  attentive  ex- 
amination, and  the  most  delicate  anatomical  operations,  can 
only  show  in  the  epidermis,  one  homogeneous  layer,  whose 
adhering  surface  becomes  insensibly  confounded  with  the  mu- 
cous body,  and  which  is  deprived  of  cellular  tissue,  of  vessels, 
and  of  nerves. 

§  306.  The  thickness  of  the  epidermis  is  but  trifling,  being 
scarcely  equal  to  the  fifth  or  sixth  part  of  that  of  the  skin.  It 
is  thicker  in  the  palm  of  the  hand,  and  the  sole  of  the  foot,  than 
any  where  else.  In  these  places,  particularly  in  mechanics, 
or  in  persons  who  walk  much,  it  appears  to  be  formed  of  seve- 
ral layers.  M.  Heusinger,*  considers  this  part  as  a  variety  of 
the  horny  tissue,  and  has  described  it  under  the  name  of  the 
callous  tissue.  The  epidermis  is  not  so  elastic  as  the  corium, 
is  very  flexible  and  easily  torn.  It  is  transparent,  and  of  a  light 
grayish  colour.  In  the  coloured  races  it  partakes  of  the  colour 
of  the  skin,  but  it  is  not  so  deep  as  the  corpus  mucosum.  The 
transparency  of  the  epidermis  is  not  every  where  the  same; 
if  we  look  at  it  against  the  light,  we  perceive  points  more 
transparent  than  others,  previously  taken  for  pores. 

§  307.  It  is  known  that  Leuwenhoeck  thought  he  had  per- 
ceived them,  and  that  he  has  figured  them.  Many  have  ad- 
mitted them  from  this,  or  from  physiological  considerations. 
But  neither  the  observations  of  M.  de  Humboldt,  made  with 
magnifying  instruments  greatly  superior  to  those  of  Leuwen- 
hoeck, nor  those  of  Seiler,  made  upon  the  epidermis  detached 
by  a  razor,  from  the  body  of  an  animal  while  sweating,  nor 
my  own,  made  by  charging  a  piece  of  epidermis  with  a  column 
of  mercury  of  about  the  weight  of  one  atmosphere,  have  been 
able  to  discover  these  pores.  Again,  observation  teaches  us 

*  System  der  Mstobgia,  von  Heusinger  Eisenach,  1822,  4to, 


OF  THE  SKIN  IN  GENERAL.  217 

that  the  epidermis  prevents,  or  greatly  moderates  evaporation 
in  the  dead  body,  and  that  those  places  which  are  deprived  of 
it,  as  well  as  the  subjacent  parts,  become  dry  with  great  ra- 
pidity. The  epidermis,  however,  permits  those  matters  to  pass 
which  the  skin  absorbs  during  life,  and  certainly  those  it  ex- 
cretes. But  what  is  more  astonishing,  is,  that  in  the  observa- 
tions of  which  we  have  just  spoken,  no  one  has  been  able  to 
perceive  even  the  openings  of  the  epidermis,  through  which 
the  hairs  pass,  those  which  correspond  to  the  sebaceous  folli- 
cles, nor  even  those  which  had  been  made  in  it  with  a  fine 
needle.  The  same  thing,  it  is  well  known,  happens  in  caout- 
chouc. Filtering  paper  presents  no  visible  pores  to  the  mi- 
croscope while  it  is  wet,  but  when  dry  they  are  very  per- 
ceptible. 

§  308.  It  being  impossible  then,  for  cutaneous  absorption 
and  perspiration,  to  depend  on  the  physical  properties  of  the 
epidermis,  an  explanation  has  been  sought  for  in  its  chemical 
properties.     The  dried  epidermis  diminishes  in  volume,  be- 
comes firmer,  more  elastic,  and  slightly  yellowish.    Macerated 
in  cold  water,  on  the  contrary,  it  swells  a  little,  becomes  soft, 
less  elastic,  whiter  and  more  opaque.     It  imbibes  this  fluid, 
however,  very  slowly,  and  it  requires  along  submersion  of  the 
hands  and  feet  in  water,  for  the  epidermis  to  absorb  a  suffi- 
ciency of  the  liquid,  to  become  white  and  opaque,  and  yet  the 
epidermis  of  these  regions  appears  to  imbibe  it  more  readily 
than  that  of  the  other  parts  of  the  body.     It  is  to  this  difficulty 
of  the  permeability  in  the  epidermis,  that  we  are  to  attribute 
the  difficulty  with  which  the  fluid  of  ampullae  escapes  during 
life,  and  the  slowness  with  which  the  skin  of  dead  bodies  dry 
even  in  the  most  arid  atmosphere,  provided  the  epidermis  re- 
mains entire.     It  resists  putrefaction  for  a  long  time;  it  has 
been  found  entire  in  tombs  at  the  expiration  of  more  than  fifty 
years.     Boiling  water  renders  the  epidermis  white,  opaque, 
and  deprives  it  of  its  elasticity  much  quicker  than  cold  water. 
Continued  ebullition  extracts  a  little  gelatine  from  it,  which 
appears  to  proceed  from  its  adhering  face;  the  residuum  does 
not  appear  to  differ  from  the  entire  epidermis.     Exposed  to 
fire  it  burns  like  horn,  and  gives  out  a  similar  odour.     Pure 


2  IS  GENERAL  ANATOMY. 

fixed  alkalies  resolve  it  completely  into  a  saponaceous  sub- 
stance. Nitric  acid  turns  it  yellow  almost  at  once,  thickens, 
softens,  and  renders  it  opaque  in  about  fifteen  minutes,  and  in 
twenty-four  hours  reduces  it  to  a  yellow  pulp.  If  ammonia  is 
applied  on  the  epidermis,  rendered  yellow  by  nitric  acid,  it 
changes  to  a  deep  orange  colour.  Now  Hatchett  has  proved 
that  similar  effects  took  place  on  coagulated  albumen.  The 
epidermis  appears  to  consist  of  a  layer  of  albuminous  mucus, 
coagulated  and  dried. 

§  309.  The  epidermis  is  neither  irritable  nor  sensible;  of  all 
parts  of  the  body  it  possesses  the  most  active  force  of  forma- 
tion; it  results  from  the  concretion  of  a  fluid  exuded  on  the 
surface  of  the  skin,  constantly  renewed,  never  absorbed,  but 
destroyed  externally  as  fast  as  it  is  produced  on  the  internal 
face. 

§  310,  Numerous  hypotheses  have  been  broached  upon  the 
formation  of  the  epidermis;  the  most  ancient,  is  that  which 
teaches  us  to  regard  it  as  the  drying  of  a  fluid  furnished  by  the 
surface  of  the  dermis.  Others,  with  Leuwenhoeck,  saw  no- 
thing in  it  but  an  expansion  of  the  vessels  of  the  skin.  Others 
again,  as  Ruysch,  made  it  to  consist  of  the  expansion  and  dry- 
ing of  the  papillae.  Heister  attributed  its  formation  to  these 
two  causes;  Morgagni  to  the  callification  or  induration  of  the 
surface  of  the  skin,  from  the  pressure  of  the  waters  of  the  am- 
nios  at  first,  and  subsequently,  from  that  of  the  atmosphere; 
and  Garangeot  to  the  induration  of  the  rete  mucosum.  All 
those  opinions,  particularly  the  first  and  the  last,  contain  some 
truth.  It  results,  in  fact,  from  an  exudation  or  excretion  of 
the  dermis.  It  is  the  indurated  surface  of  the  corpus  muco- 
sum; so  that  from  the  dermis  to  the  free  surface  of  the  epider- 
mis, there  is  a  successive  deterioration  of  organization,  and  of 
vitality,  which  makes  a  kind  of  varnish  of  the  epidermis,  and 
participating  in  organization  and  life,  only  by  its  origin,  a  cir- 
cumstance which  renders  it  very  fit  to  support  the  action  of 
external  bodies,  and  to  protect  the  vessels,  nerves,  and  other 
parts  of  the  skin. 

§311.  The  skin,  formed  by  the  dermis,  the  vessels  and  the 
nerves  which  are  distributed  through  its  thickness,  and  par- 


OF  THE  SKIN  IN  GENERAL.  219 

ticularly  on  its  superficial  face;  by  the  epidermis,  of  which  we 
have  been  speaking,  and  by  the  intermediate  mucous  body, 
offering,  thus,  a  diminution  of  organization,  and  of  vitality, 
from  the  dermis  to  the  epidermis,  partakes  of  the  physical, 
chemical,  and  vital  properties  of  these  various  parts.  It  is  the 
same  with  respect  to  its  functions  or  organic  actions. 

§  312.  The  skin,  on  account  of  the  dry  and  slightly  permea- 
ble epidermis,  which  makes  a  part  of  it,  is  not  so  well  adapted 
for  absorption  and  secretion  as  the  mucous  membrane. 

The  skin  being  furnished  with  its  epidermis,  in  a  state  of 
integrity,  cutaneous,  or  as  it  is  also  called,  cuticular,  absorp- 
tion, is  in  fact,  to  this  day,  a  subject  of  doubt  and  discussion 
among  physiologists.  To  decide  this  question  between  Seguin, 
Currie,  Klapp,  Rousseau,  Dangerfield,  Chapman,  Gordon,  Ma- 
gendie,  &c. ,  whose  observations  and  experiments  go  to  dis- 
prove the  existence  of  cutaneous  absorption,  and  Keil,  Haller, 
Percival,  Home,  Ouikshank,  Watson,  Forci,  Abernethy,  Bi- 
chat,  Duncan,  Kelly,  Bradner,  Stewart,  Sewall,  &c.,  and  M. 
Young  in  particular,  whose  experiments  and  observations  are 
in  favour  of  this  absorption,  we  must  abstract  all  those  cases, 
and  they  are  numerous,  in  which  absorption  may  have  taken 
place  by  respiration,  as  well  as  by  the  skin:  those  in  which  the 
epidermis  may  have  been  softened,  altered,  or  abraded  by  con- 
tinued applications  to  its  surface,  or  by  repeated  rubbings,  un- 
der which  circumstances,  absorption  is  no  longer  cuticular,  but 
of  the  same  kind  to  that  which  takes  place  in  the  mucous  mem- 
brane, or  by  inoculation,  when  the  matter  is  carried  through 
the  divided  epidermis  into  the  corpus  mucosum,and  even  into 
the  dermis,  both  parts  being  eminently  absorbent.  When  this  is 
done,  there  remains  a  small  number  of  facts,  which  show,  that 
certain  substances  are  absorbed  by  the  skin,  through  the  epi- 
dermis, in  its  entire  state,  but  that  this  membrane  is  truly  an 
obstacle  that  very  often  prevents  the  absorbent  power  of  the 
external  tegument. 

§  313.  The  skin  is  also  an  organ  of  secretion  and  excretion. 
Two  kinds  of  well  known  extrinsic  secretion  take  place  in 
this  membrane,  cutaneous  perspiration  and  the  sebaceous  fol- 
licular  secretion.  Perspiration  is  sometimes  vaporous  and 


220  GENERAL  ANATOMY. 

insensible,  and  at  others  liquid  and  visible;  in  the  latter  cat>e  11 
is  called  sweat.  This  secretion  is  continual,  and  probably,  es- 
sentially the  same  in  both  cases;  but  in  the  first  it  is  insensible 
on  account  of  its  vaporisation.  The  secretion  takes  place  in 
the  skin,  but  by  what  vessels,  we  do  not  know;  as  to  the 
ways  by  which  it  traverses  the  corpus  mucosum  and  the  epi- 
dermis, we  are  totally  ignorant.  It  is  likely  that  the  perspi- 
ratory secretion  takes  places  in  the  bottom  of  the  microscopic 
incisures  and  depressions  of  the  epidermis,  a  place  where  it 
is  the  least  dry.  The  quantity  of  this  secreted  matter  is  very 
great,  but  difficult  to  determine.  Sanctorius,  whose  experi- 
ments are  so  celebrated,  had  observed,  that  he  lost  five-eighths 
of  the  whole  of  his  aliment  by  pulmonary  and  cutaneous  per- 
spiration. Among  those  who  have  repeated  his  experiments, 
Lavoisier  and  M.  S6guin  have  made  this  distinction;  they 
found  that  the  cutaneous  perspiration,  is  to  the  pulmonary 
perspiration  on  an  average,  as  eleven  is  to  seven.  Cruikshank 
has  tried  to  determine  its  nature,  and  found  that  it  had  all  the 
properties  of  water,  containing  carbonic  acid  and  an  odorous 
animal  matter. 

When  the  matter  of  perspiration  is  collected  in  the  form  of 
sweat,  we  see  it  appear  on  the  surface  of  the  skin  in  small 
drops,  upon  which  Leuwenhoeck  has  made  some  interesting 
observations.  Human  sweat  in  a  state  of  health  is  always 
acid,  saltish,  and  odorous.  According  to  Theuard  it  is  formed 
of  much  water,  a  small  quantity  of  acetic  acid,  of  hydro  chlo- 
rate of  soda,  and  perhaps  of  potash,  very  little  earthy  phos- 
phate, an  atom  of  the  oxide  of  iron,  and  of  an  inappreciable 
quantity  of  animal  matter.  M.  Berzelius  considers  it  as  water 
holding  in  solution  the  hydro  chlorates  of  potash  and  soda, 
lactic  acid,  lactate  of  soda,  and  a  little  animal  matter. 

The  cutaneous  perspiration,  either  sensible  or  insensible, 
must  be  regarded  as  one  of  the  most  important  excretions  of 
the  organism.  It  is,  besides,  a  potent  mean  of  refrigeration 
and  of  resistance  against  too  elevated  a  temperature.  This 
function  presents  numerous  varieties,  according  to  the  age, 
sex,  the  individual,  external  circumstances,  the  state  of  the 
other  functions,  the  action  of  ingested  or  applied  substances, 


OP  THE  SKIN  IN  GENERAL.  221 

diseases,  &c.     It  exercises  great  influence  over  the  other  func- 
tions. 

§  314.  It  is  admitted  that  gaseous  secretions  and  absorptions, 
analogous  to  those  of  the  lungs,  and  constituting  a  sort  of  cu- 
taneous respiration,  take  place  through  the  skin.  Thus,  Spal- 
lanzani  in  the  mollusca,  Edwards  in  reptiles,  and  Jurine  even 
in  man,  have  seen  the  skin  absorb  oxygen.  According  to 
various  natural  philosophers  and  physiologists,  gases  are  also 
excreted  from  the  skin;  but  objections  and  experiments  can 
be  opposed  to  these  assertions;  the  experiments  of  Priestly 
may  also  be  opposed  to  those  of  Cruikshank,  of  Dr.  McKenzie 
and  of  M.  Ellis,  which  seem  to  favour  the  theory  of  a  cutane- 
ous excretion  of  carbone,  which  combines  with  the  oxygen  of 
the  atmosphere  to  form  carbonic  acid.  It  is  at  any  rate  cer- 
tain, that  if  in  man,  whose  epidermis  is  dry,  and  whose  pul- 
monary respiration  is  very  great,  the  air  exercises  a  vivifying 
action  upon  the  blood  which  circulates  in  the  skin,  this  action 
can  in  nowise  supply  that  of  the  lungs. 

§  315.  The  skin  excretes  an  oily  matter,*  that  Cruikshank 
succeeded  in  obtaining,  in  the  form  of  black  tears,  on  the  sur- 
face of  a  knitted  woollen  waistcoat  that  he  wore  night  and 
day  for  a  month  in  the  heat  of  summer.  Rubbed  on  paper, 
this  matter  acts  like  fat,  it  burns  with  a  white  flame  and  leaves 
a  carbonaceous  residuum.  It  is  uncertain  whether  this  oil, 
which  has  been  said  to  be  subcutaneous  fat  transuding  through 
the  skin,  is  produced  by  the  same  channels  as  the  preceding, 
or  the  following. 

§  316.  The  cutaneous  follicles  secrete  a  sebaceous  matter. 
This  matter  is  thick,  not  glutinous,  without  any  fibrous  ap- 
pearance when  indurated ;  by  suspension  in  water,  by  tritura- 
tion,  it  forms  a  sort  of  emulsion,  but  it  does  not  dissolve. 
Exposed  to  fire,  it  does  not  melt;  it  burns,  leaving  much  char- 
coal. It  chiefly  contains  cerumen,  a  proportion  of  oil,  that 
may  be  separated  from  it  by  blotting  paper.  This  matter  is 
formed  in  the  sebaceous  follicles,  whence  by  pressure  it  may 
be  forced  out  in  the  form  of  little  worms,  and  whence  it  na- 

*  Ludwig  and  Grutzmacher,  de  Humore  cutem  inungente.  Lipsiac,  1748, 


222  GENERAL  ANATOMY. 

\ 

turally  oozes,  to  anoint  the  neighbouring  skin,  and  principally 
to  defend  it  from  the  action  of  water  and  excrementitious  hu- 
mours. 

It  is  these  three  matters  united  which  constitute  the  cutane- 
ous excretion,  an  excretion  that  is  very  abundant,  a  part  oi' 
which  is  continually  evaporated,  while  the  more  fixed  portions 
cover  the  skin,  from  which  they  are  subsequently  detached 
in  the  form  of  dirt.  To  these  excretions  must  be  added  that 
of  the  epidermis,  which  is  continually  wearing  away  on  its 
superficial  face,  and  is  as  regularly  reproduced  on  the  opposite 
one. 

§  317.  The  skin  is  an  organ  of  sensation.  It  is  still  more 
than  the  other  tegumentary  membrane,  the  organ  of  tact,  ge- 
neral and  passive,  which  makes  us  sensible  of  the  presence  of 
bodies,  their  temperature,  &c.;  moreover,  and  particularly  in 
certain  places,  being  provided  with  many  vessels  and  nerves, 
and  well  fitted  for  adaptation  to  the  forms  of  bodies,  it  is  a 
special  and  active  organ  of  touch.  The  tact  and  touch  are  so 
much  the  more  delicate,  as  the  papillse  are  more  developed 
and  less  covered. 

§  318.  Finally,  the  skin  is  a  defensive  organ,  not  very  effi- 
cient in  man,  but  greatly  so  in  particular  animals,  where  the 
mucous  body  is  the  seat  of  horny  and  calcareous  incrustations. 
It  is  evident  that  this  organ,  whose  functions  are  as  multiplied 
as  its  texture  is  complex,  can  not  have  one  of  its  parts  or  one 
of  its  functions  greatly  developed,  but  at  the  expense  of  the 
others;  consequently  the  thicker  and  more  protecting  the 
corpus  mucosum  and  epidermis,  the  duller  is  the  .sense  of 
touch. 

§  319.  The  embryo,  until  the  middle  of  the  second  month, 
has  no  distinct  skin.  About  this  period,  according  to  Auten- 
rieth,  the  epidermis  begins  to  appear.  Until  half  the  term  of 
gestation,  the  skin  remains  thin,  colourless  and  transparent: 
it  then  assumes  a  rosy  hue  until  about  the  eighth  month ;  at 
this  epoch  it  becomes  pale,  except  in  the  folds.  In  about  four 
months  and  a  half,  the  sebaceous  follicles  begin  to  be  visible, 
on  the  head  first,  and  subsequently  in  the  other  parts  of  the 
body  :  at  seven  months,  the  sebaceous  or  caseiform  covering 


OF  THE  SKIN  IN  GENERAL.  223 

/ 

of  the  skin,  begins  to  show  itself:  at  birth  the  skin  is  covered 
with  it,  and  is  of  a  rosy  white;  after  birth,  the  skin  soon  ac- 
quires the  colour  peculiar  to  the  race  and  increases  in  thick- 
ness and  strength  until  the  adult  age;  in  old  age  it  becomes 
dry,  wrinkled,  and  gradually  loses  its  colour. 

The  skin  is  thinner,  finer  and  softer  in  females;  but  these 
characters  sometimes  disappear  after  the  age  of  puberty. 

§  320.  The  differences  presented  by  the  skin  in  the  various 
races,  have  been  already  noticed  [112,  116.]  Individuals  of 
the  coloured  races  and  even  negroes  are  born  with  nearly 
the  same  colour  as  whites.  The  colour  begins  to  show  it- 
self from  the  moment  the  child  breathes,  but  particularly, 
about  the  third  day  after  birth,  round  the  nails,  nipples,  eyes, 
anus,  and  the  organs  of  copulation;  by  the  seventh  day  the  co- 
louring is  everywhere  extended,  the  palm  of  the  hand  and 
sole  of  the  foot  excepted,  which  remain  whitish.  The  colour 
is  not  intense  during  the  first  year,  it  afterwards  augments, 
and  continues  for  the  greater  portion  of  life  to  diminish  in  old 
age.  The  odour  of  the  skin,  like  its  colour,  varies  in  the  races. 
Independently  of  national  varieties,  they  are  many  among  in- 
dividuals. 

§  321.  The  morbid  alterations  of  the  skin  are  extremely 
numerous.  We  have  already  spoken  of  cicatrices  or  of  acci- 
dental reproductions  of  this  membrane  [258.]  The  new  tis- 
sue is  analogous  to  the  old  one,  but  is  not  the  same.  The  der- 
mis  is  more  dense,  less  areolar,  more  compact,  less  vascular, 
and  less  papillary  than  that  of  the  skin.  The  epidermis  evi- 
dently exists  on  it,  though  quite  recently  this  has  been  denied; 
it  is  an  error.  The  corpus  mucosum  exists  there  also,  as  well 
as  its  coloured  layer;  and  Camper  is  wrong  when  he  asserts, 
that  the  cicatrices  of  the  negro  are  white;  the  hue  is  merely  a 
little  different.  Horny  productions  sometimes  form  upon  the 
cicatrices;  these  accidental  teguments  are  very  liable  to  ul- 
cerate. 

Accidental  skin  is  sometimes  found  in  the  cysts  of  the  ova- 
ries, it  is  probably  an  imperfect  production  of  a  foetus,  either 
engendered,  or  enveloped  in  the  foetal  state,  by  the  individual 
which  contains  them. 
30 


224  GENERAL  ANATOMY. 

§  322.  The  skin  sometimes  presents  primitive  vices  of  con- 
formation, either  by  deficiency,  which  causes  divisions  or  de- 
nudations in  the  foetus,  or  by  excess,  which  forms  folds  or  sacs 
more  or  less  extensive.  It  presents  also  acquired  vices  of  con- 
formation; its  distention,  carried  to  a  great  degree,  as  for  in- 
stance in  pregnancy,  separates,  loosens  the  fibres  of  the  dermis, 
and  produces  welts,  after  delivery,  which  at  first  are  brown  or 
blackish,  that  afterwards  become  and  remain  more  white  and 
shining  than  the  rest  of  the  skin.  A  more  moderate  and  more 
continued  degree  of  distention,  produces  a  loss  of  its  elasticity 
and  retractility,  and  when  it  is  removed  leaves  wrinkles  more 
or  less  deep. 

§  323.  The  skin  is  the  frequent  seat  of  congestions,  dis- 
charges, and  inflammations,  acute  and  chronic,  whose  various 
effects,  either  on  the  texture  of  the  membrane,  on  its  colour,  or 
on  the  products  of  its  secretion,  have  given  rise  to  the  esta- 
blishment of  fifty  genera,  and  more  than  a  hundred  species  of 
cutaneous  diseases,  consisting  of  pimples,  scales,  eruptions, 
ampullae,  pustules,  vesicles,  tubercles,  spots,  &c.,  respecting 
which  the  works  of  Plenck,  Alibert,  Willan,  and  Bateman, 
may  be  consulted  with  advantage. 

§  324.  The  retention  of  the  sebaceous  matter,  and  its  accu- 
mulation in  the  follicles,  give  rise  to  the  formation  of  tumours 
called  pimples,  when  they  are  small,  and  which,  when  large, 
are  confounded  with  the  encysted  tumours  under  the  names 
of  wens,  meliceris,  steatomatous  tumours,  and  atheromse. 
When  the  tumour  is  small,  and  the  orifice  of  the  follicle  is  not 
obliterated,  the  sebaceous  matter  may  be  forced  out  of  it  by 
pressure  in  the  form  of  a  worm,  a  circumstance,  which  has  led 
some  inattentive  observers,  who  are  fond  of  the  marvellous, 
into  error.  When,  on  the  contrary,  the  tumour  has  greatly  in- 
creased, and  grown  voluminous  under  the  skin,  and  its  orifice 
is  not  apparent,  it  greatly  resembles  a  cyst;  but  by  dissecting 
it  with  care,  traces  of  the  orifice  may  be  found  in  the  point 
where  it  holds  to  the  skin;  and  if  we  split  the  skin  and  the  tu- 
mour in  that  point,  we  can  easily  follow  the  epidermis,  which 
is  reflected  from  the  surface  of  the  first  into  the  cavity  of  the 
second.  Whether  the  matter  contained  in  it,  resemble  honey, 


OF  THE  SKIN  IN  GENERAL.  225 

bouilli,  or  tallow,  it  is  always  sufficiently  like  the  matter  of 
the  sebaceous  follicles,  to  be  recognised. 

§  325.  Various  accidental  productions,  either  analogous  or 
morbid,  are  observed  in  the  skin.     This  membrane  is  some- 
times raised  up  by  a  more  or  less  great,  and  sometimes,  an  in- 
numerable quantity  of  tumours,  very  various  as  to  size,  and 
formed  by  the  accidental  production  of  a  white  fibrous  tissue, 
that  is  much  more  compact  than  the  cellular  tissue,  and  looser 
than  the  ligamentous  tissue,  one  that  is  often  found  in  polypi,  and 
particularly  in  the  sub-mucous  tumours  of  the  vagina  and  vulva. 
§  326.  The  colour  of  the  skin  presents  various  changes.  That 
of  the  albinoes  is  the  most  singular:  their  skin  is  of  a  dead,  or 
rosy  white,  very  different  from  the  white  of  Europeans;  their 
hairs  are  transparent,  whitish,  or  rather  colourless;  the  iris  of 
the  eye  is  of  a  pale  rose,  and  the  opening  of  the  pupil  red, 
which  is  owing  to  the  absence  of  the  pigment  of  the  choroides, 
and  of  the  uvea.     The  functions  of  the  skin,  and  particularly 
of  the  eyes,  feel  the  effects  of  this  alteration,  which  has  been 
attributed  to  the  absence  of  the  mucous  body,  and  which,  at 
any  rate,  certainly  depends  upon  that  of  the  colouring  matter 
of  the  skin  and  its  appendages;  it  is  wrong  to  regard  it  as  the 
effect  of  a  leprosy,  a  cachexia,  or  as  a  state  of -disease;  it  is  an 
error  of  Blumenbach  and  Winterbottom,  sufficiently  refuted  by 
the  observations  of  Jefferson,  who  expressly  declares,  that  all 
the  individuals  of  this  kind  that  he  saw  were  well  made,  strong 
and  healthy.     This  alteration  is  found  in  all  the  races  of  the 
human  family,  in  every  part  of  the  globe,  and  in  a  great  many 
genera  of  animals.     It  begins  at  birth,  continues  through  life, 
and  is  transmitted  by  generation.     The  union  of  an  albino  and 
of  a  coloured  person,  generally  produces  coloured  offspring, 
and  sometimes  albinoes.     It  does  not,  however,  constitute  a 
race  in  the  human  species,  but  is  found  sporadically,  or  as  ac- 
cidental varieties. 

The  noevi  and  marks  on  the  skin,  consist,  in  some  cases,  of  a 
coloured  patch  of  the  mucous  body,  which  in  this  case  is 
usually  visibly  thicker  in  that  point  than  elsewhere;  in  others, 
they  consist  in  an  erectile  disposition  of  the  cutaneous  vessels, 
which  will  be  described  hereafter.  (Chap.  iv. ) 


226  GENERAL  ANATOMY. 

The  colour  of  the  skin  is  also  subject  to  accidental  altera- 
tions: thus  we  see  individuals  among  the  whites  become  brown, 
or  perfectly  black,  in  places  of  more  or  less  extent.  Whites 
and  blacks  also  become  albinoes  in  points  of  the  skin  more  or 
less  extensive. 

May  not  the  melanosis  which  usually  coincides  with  the  dis- 
colouration of  the  skin,  and  which  is  so  often  observed  in  white 
hairs,  depend  upon  an  aberration  of  the  pigment  of  the  skin? 

Horny  productions,  which  project  more  or  less  from  the 
surface  of  the  skin,  are  sometimes  found  in  the  corpus  muco- 
sum;  these  productions  being  analogous  to  the  nails,  will  be 
described  after  these  appendages  of  the  skin. 


ARTICLE  II. 
OF   THE  APPENDAGES  OF  THE 

§  327.  The  nails  and  hairs  are  the  only  appendages  of  the 
human  skin;  in  animals,  on  the  contrary,  they  exist  in  great 
numoers  and  variety.  It  is  an  error  to  consider  these  parts  as 
appendages  of  the  epidermis  alone,  for  they  are  connected  with 
the  whole  skin. 

1.   OF  THE  NAILS.* 

§  328.  The  nails,  ungues,  are  horny  scales  which  cover  the 
skin  of  the  last  phalanx  of  the  fingers  and  toes,  on  the  side  of 
the  extensors. 

Three  parts  are  noticed  in  the  nail,  viz:  the  root,  the  body, 
and  the  free  extremity. 

The  root  or  adhering  extremity,  is  the  fifth  or  sixth  part  of 
the  length  of  the  nail;  it  is  the  thinnest  part  of  it;  it  is  received 
nto  a  groove  in  the  skin,  and  is  of  a  white  colour.  The  body, 

*  Frankeneau,  de  Unguibus.  Jenoe,  1796. — Ludvvig,  de  ortu  et  structure! 
unguium.  Lipsiae,  1748. — B.  S.  Albinus,  in  Arinot.  acad.  lib.  ii.  cap.  xiv. 
de  Ungue  humano,  ejusque  reticulo  &?c.,  et  cap.  xv.  de  Natura  unguis. — Bose, 
de  Unguifas  humanit.  Lips.  1773.— Haase,  de  Nutritione  unguium.  Lips. 
1774. 


OP  THE  NAILS.  227 

or  middle  part,  is  of  a  middling  thickness;  its  external  free 
face  is  smooth,  presents  longitudinal  furrows,  more  or  less 
deep,  and  is  transversely  convex.  Its  opposite  face  adheres 
closely  to  the  skin;  the  posterior  part  of  the  body  of  the  nail, 
for  a  small  extent  and  which  gradually  diminishes  in  proceed- 
ing from  the  thumb  to  the  fourth  or  little  finger,  is  white; 
this  semi-lunar  portion  has  been  called  the  lunula;  the  other 
part  appears  reddish  on  account  of  its  transparency,  which 
renders  visible  the  colour  of  the  skin.  The  free  extremity  of 
the  nail  is  its  thickest  part;  it  projects  beyond  the  end  of  the 
finger  and  shows  a  tendency,  although  but  slight,  to  curve  into 
a  sort  of  hook. 

§  329.  The  connexion  of  the  nail  with  the  dermis  and  epi- 
dermis is  effected  in  the  following  manner:  the  dermis  is  thick- 
ened and  very  papillar  beneath  the  body  of  the  nail,  under  the 
lunule  excepted;  the  papillae  are  arranged  in  linear  series 
like  very  delicate  and  closely  approximated  longitudinal  sulci. 
The  corresponding  face  of  the  nail  is  soft,  pulpy  and  furnished 
with  longitudinal  grooves,  which  receive  and  adhere  very 
closely  to  the  papillary  furrows  of  the  dermis.  Their  separa- 
tion, however,  in  the  dead  body,  is  produced  by  the  same 
causes  that  separate  the  epidermis  and  mucous  body  from  the 
dermis.  The  adhering  extremity  of  the  nail,  very  thin  and  very 
soft,  is  received  into  the  bottom  of  a  fold  of  the  dermis,  de- 
prived of  epidermis.  Under  the  small  and  irregularly  deve- 
loped nails  of  the  last  toes,  the  papillae  of  the  dermis  are  ar- 
ranged irregularly  and  not  in  linear  series;  the  adhering  face 
of  the  nail  presents  the  same  irregular  disposition  for  the  re- 
ception of  the  papillae. 

§  330.  The  epidermis  having  arrived  near  the  root  of  the 
nail,  is  reflected  with  the  dermis  to  the  bottom  of  the  furrow. 
There  the  dermis  passes  under  the  nail;  the  epidermis  on  the 
contrary  is  reflected  over  its  root,  and  is  prolonged  over  its 
external  face,  which  it  thus  covers  with  a  very  thin  lamina, 
that  is  confounded  with  it.  At  the  free  extremity  of  the  nail 
the  epidermis  of  the  end  of  the  finger  is  reflected  under  its 
deep  face  and  is  united  to  the  free  part  of  that  face.  On  the 


228  GENERAL  ANATOMY. 

sides  there  is,  behind,  a  disposition  analogous  to  that  at  the 
root,  and  before,  to  that  of  its  free  extremity. 

The  nails  have  no  connections  besides  those  just  described. 
It  is  from  want  of  observation  that  some  anatomists  have 
admitted  them  to  have  others  with  the  periosteum  and  the 
tendons. 

§  331.  Some  have  admitted,  with  Blaucardi,  that  the  nails 
are  formed  of  agglutinated  hairs;  others,  that  they  result  from 
the  super-position  of  scales  or  horny  lamina,  the  uppermost 
of  which  is  the  whole  length  of  the  nail,  while  the  others  suc- 
cessively diminish  in  length,  which  occasions  a  regularlj 
increasing  thickness  from  the  root  to  the  free  extremity. 
These  are  rather  ways  of  accounting  for  the  mode  of  the  forma- 
tion of  the  nails,  than  results  of  observation,  which  in  fact  dis- 
covers in  the  nails  a  horny  substance  only,  hard  and  dry  ex- 
ternally, and  mucous  in  the  interior.  Neither  vessels  nor 
nerves  are  to  be  found  in  them.  They  consist  in  a  thick  and 
horny  layer  of  the  mucous  body  of  the  skin. 

§332.  The  nails  are  diaphanous,  flexible,  and  elastic;  they 
may  be  torn  crosswise,  notwithstanding  their  fibrous  appear- 
ance in  another  direction.     Their  chemical  properties  are  those 
of  coagulated  albumen;  they  appear  also  to  contain  a  little 
phosphate  of  lime;  they  are  very  similar  to  horn.    They  are 
totally  deprived  of  irritability  and  sensibility.     The  force  of 
formation  or  a  continual  growth  by  a  sort  of  vegetation,  is  the 
only  organic  and  vital  phenomenon  observed  in  them;  even 
this  is  foreign  to  them.     The  materials  of  which  they  are 
formed,  are  continually  and  proportionably  secreted  and  ex- 
creted by  the  dermis:  this  matter  applied  to  the  extremity 
and  adhering  face  of  the  nail,  like  that  of  the  secretion  of  the 
silk-worm,  concreting  as  fast  as  it  is  excreted,  and  being  con- 
tinually added  to  that  which  has  preceded  it,  pushes  it  before 
it,  and  thus  lengthens  the  nail  by  juxta-position,  and  not  by 
intus-susception.     It  is  then  a  true  excretion,  whose  materials, 
once  deposited,  are  never  absorbed.     The  nails  arm,  support 
and  protect  the  extremity  of  the  fingers  and  toes. 

§  333.  The  nails  begin  to  appear  about  the  middle  of  the 
foetal,  term:  even  at  birth  they  are  still  very  imperfect.     In 


OF  THE  NAILS.  229 

the  coloured  races,  the  colour  is  subjacent  to  the  nail.  In 
many  animals,  on  the  contrary,  the  coloured  layer  of  the  mu- 
cous body  is  confounded  with  the  horny  layer  in  the  compo- 
sition of  the  nails  and  similar  parts.  The  parts  most  analo- 
gous to  the  nails  of  man  are  the  claws  of  the  carnivora,  &c., 
which  surround  the  dorsal  face  and  the  sides  of  the  last  pha- 
lanx, and  are  curved  towards  the  sole;  and  the  hoofs  of  the 
ruminantia,  &c.,  which  envelop  the  whole  extremity  of  the 
last  phalanx.  The  nails  of  the  human  foot  have  sometimes  a 
considerable  growth,  and  assume  a  direction  that  approximates 
them  to  claws. 

§  334.  The  alterations*  attributed  to  the  nails,  are,  in  fact, 
utterly  foreign  to  them,  and  depend  wholly  on  the  skin  that 
produces  them.  It  is  the  same  with  respect  to  accidental 
horny  productions:  it  is  in  the  subjacent  tissue,  that  we  must 
seek  for  their  origin. 

When  a  nail  has  been  torn  by  violence,  or  detached  by  dis- 
ease from  the  subjacent  skin,  it  grows  again  slowly,  and  differs 
more  or  less  from  the  primitive  one,  just  as  the  affection  of 
the  skin  continues  more  or  less,  at  the  time  of  its  second 
growth. 

Horny  laminae,  more  or  less  analogous  to  the  nails,  are 
formed  upon  cicatrices,  the  ends  of  the  toes  and  other  places 
exposed  to  pressure  or  violent  and  reiterated  friction,  such 
are  callosities,  &c.  Simple  ichthyosis,  differs  from  them  only 
in  its  extent  and  our  ignorance  of  its  cause. 

Corns  also  consist  of  round,  hard,  small,  accidental  horny, 
productions,  which  by  the  compression  they  transmit,  irritate, 
inflame  and  sometimes  pierce  the  skin,  and  even  affect  the 
bones  and  subjacent  articulations. 

Horns  or  horny  conoid  productions  more  or  less  elongated, 
have  been  very  often  observed  from  the  earliest  ages  on  al- 
most all  parts  of  the  skin.  Sometimes  a  single  one  of  these 
excrescences  exist  on  an  individual  and  is  developed  on  a  ci- 
catrix,  in  a  sebaceous  follicle,  or  on  some  point  of  the  skin, 
that  has  been  previously  altered,  or  even  without  any  thing 

*  Plenck,  de  marbis  unguium,  in  dodrind  de  rnorbis  cutancis. 


230  GENERAL  ANATOMY. 

particular  in  the  skin  having  been  marked;  at  others,  produc- 
tions of  this  kind  exist  on  almost  every  part  of  the  skin,  con- 
stituting a  species  of  ichthyosis. 

The  warts  of  the  skin  and  those  of  the  mucous  membrane, 
may  be  approximated  to  the  accidental  horny  productions,  and 
be  considered  as  an  imperfect  horny  tissue,  both  of  them  par- 
ticipating in  the  horny  tissue,  and  in  that  of  the  membrane. 

In  certain  general  as  well  as  local  affections  of  the  skin,  as 
well  as  the  habitual  contact  of  acids,  &c.  as  happens  in  some 
professions,  the  nails  soften,  become  fleshy,  and  imperfect 
horny  tissue,  vegetate  irregularly,  present  excrescences,  be- 
come dry,  and  fragile.  They  always  partake  of  the  healthy 
or  diseased  state  of  the  skin  of  which  they  are  a  production. 
Inverted  toe  nail  is  merely  the  mechanical  cause  of  an  inflam- 
mation of  the  skin. 

II.    OF  THE  HAIRS.* 

§  335.  Hairs,  pili9  crines,  are  horny  filaments,  generally 
fine  and  long,  which  in  a  greater  or  less  number  cover  almost 
all  parts  of  the  skin,  except  the  palm  of  the  hand  and  the  sole 
of  the  foot. 

Each  hair  consists  of  a  bulb  and  stem,  and  the  texture  of 
each  of  these  parts  is  tolerably  complex,  particularly  distin- 
guishable in  their  most  voluminous  points. 

336.  The  bulb  or  follicle  of  a  hair,  which  Malpighi  com- 
pared to  the  vases  in  which  gardeners  plant  vegetables,  and 
which  has  been  ably  described  by  Chirac,  is  situated  in  the 
thickness  of  the  dermis  or  under  it;  it  is  of  an  ovoid  form;  by 
one  of  its  extremities,  which  penetrates  obliquely  through  the 
skin,  it  communicates  with  the  surface  of  that  membrane;  and 

*  P.  Chirac,  Leitre  tcriie  a  M.  Regis  sur  la  structure  des  cheveux.  Mont- 
pellier,  1688. — M.  Malpig-hi,  de  Pills,  ols.  in  op.  posth.—  WithofF,  JLnatome. 
pili  humani.  Duisb.  1750  et  in  Comm.  soc.  sclent.  Getting1.  1753. — ,T.  H. 
Kniphof  de  pibrum  usu.  Erf.  1754. — Duverney,  (Euvres  anatom.  Paris, 
1761. — Albinus,  Acad,  annot.  lib.  iv.  chap.  ix. — T.  P.  PfafF,  de  variet.  pilor. 
natural  et  prseternat.  Halae,  1796. — Car.  Asm.  Rudolphi,  Diss.  depilorum 
structura,  Gryphiswald,  1806. — Gautier,  L.  c. — Heusinger,  L,  c.  &c. 


OP  THE  HAIRS.  231 

by  the  other,  which  is  deep  and  furnished  with  implanted  fila- 
ments like  roots,  it  is  plunged  into  the  sub-cutaneous  cellular 
tissue.  Externally,  it  is.  formed  by  a  capsular,  firm,  coria- 
cious,  white  membrane,  which  is  continuous  with  the  dermis 
by  its  superficial  extremity.  Inside  this  membrane  is  another, 
thinner,  soft,  reddish,  or  variously  coloured,  and  which  appears 
to  be  a  continuation  of  the  mucous  body.  The  cavity  of  this 
membranous  follicle  is  filled  in  a  great  measure  by  a  bulb  or 
conical  papilla,  adhering  by  its  base  to  the  bottom  of  the  cavi- 
ty and  free  at  its  summit,  which  rises  towards  the  orifice  of 
the  follicle. 

Blood  vessels  reach  the  papillae,  according  to  Gautier,  by 
the  mouth  of  the  bulb,  creeping  between  these  two  membran- 
ous layers,  and  according  to  my  own  observations,  by  the  bot- 
tom. By  dissection  I  have  also  followed  nervous  threads  even 
into  the  root  of  the  follicle,  which  I  consequently  consider  as 
being  formed  by  vessels,  nerves  and  cellular  tissue. 

The  bulbs  of  the  hairs,  then,  seem  to  consist  in  a  little  piece 
of  excavated  skin,  depressed  or  doubled  over,  surmounted  by 
a  papilla,  and  furnished  with  nerves  and  vessels,  which,  in 
comparison  with  the  smallness  of  the  space  where  they  are 
distributed,  are  voluminous. 

In  the  thickness  of  the  neck  of  this  piliferous  bulb,  we  find 
several  little  sebaceous  follicles,  circularly  arranged. 

§  237.  The  stem  of  the  hair  is  planted  by  one  of  its  extremi- 
ties in  the  piliferous  bulb,  and  is  free  for  the  rest  of  its  extent. 
Its  form  is  conoid,  its  free  extremity  being  a  little  thinner 
than  the  rest.  Its  length  is  very  variable,  its  thickness  like- 
wise. The  base  is  hollow  and  lodged  in  the  bulb  where  it 
embraces  the  papilla;  the  summit  is  often  split;  whatever  "be 
the  colour  of  the  hair,  its  root  is  always  white  and  diaphanous; 
the  portion  contained  within  the  bulb  is  always  softer  than  the 
remainder,  its  most  inferior  portion,  that  which  covers  the 
papillae,  is  perfectly  fluid.  It  has  been  said,  that  the  surface 
of  the  hair  was  scaly,  or  covered  with  microscopic  asperities, 
free  near  the  summit,  and  adherent  at  the  root;  I  have  never 
been  able  to  see  them. 

§  338.  The  connexion  of  the  hair  with  the  skin  is  effected 
31 


232  GENERAL  ANAT6MY. 

as  follows:  it  is  attached  by  its  base,  which  is  hollow,  to  the 
surface  of  the  papilla;  in  addition  to  this,  the  epidermis,  after 
being  brought  from  the  surface  of  the  skin  to  the  mouth  of  the 
bulb,  is  reflected  on  the  base  of  the  hair,  is  united  to,  and  con- 
founded with  its  surface;  the  hair  is  thus  strongly  connected 
with  the  skin,  and  can  not  be  drawn  with  any  force,  without 
occasioning  pain;  the  separation  of  the  hair  in  the  dead  body, 
is  effected  by  the  same  causes,  which  detach  the  nails  and  epi- 
dermis from  the  skin. 

§  339.  The  stem  of  a  hair  consists  of  a  horny  sheath  that  is 
diaphanous,  and  nearly  colourless,  and  of  an  internal  coloured 
substance,  generally  described  as  consisting  of  a  certain  num- 
ber of  filaments,  said  to  be  from  five  to  ten,  moistened  with  a 
colouring  matter;  some  have  asserted  this  sheath  is  filled  with 
a  spongy  substance  similar  to  that  found  in  the  stems  of  fea- 
thers; others  have  pretended  that  the  internal  filaments  are 
vascular;  it  has  also  been  affirmed  that  a  hair  consists  of  one, 
single,  homogeneous,  horny  filament,  which  is  not  probable; 
Mascagni  states  it  to  be  entirely  formed  of  absorbent  vessels. 
It  appears,  on  the  contrary,  that  the  hairs,  like  the  epidermis 
and  horn,  are  totally  deprived  of  vessels  and  nerves;  that  they 
simply  consist  in  a  prolongation  of  the  two  layers  of  the  cor- 
pus mucosum,  the  horny  layer, and  the  coloured  layer,  to  which 
is  joined  the  epidermis. 

§  340.  The  colour  of  the  hairs  generally,  corresponds  to  that 
of  the  skin  and  eyes.  In  those  individuals  who  have  coloured 
spots,  or  albinous  spots,  the  hairs  are  coloured  in  the  former, 
and  white  or  colourless  in  the  latter.  They  are  very  strong, 
and  support  considerable  weight  without  breaking.  They  are 
easily  torn  or  split  lengthwise.  They  are  very  hygroscopic, 
moisture  swells  and  lengthens  them,  dryness  shortens  them: 
Saussure  has  profited  by  this  phenomenon  in  the  construction 
of  the  hygrometer  that  bears  his  name.  They  are  idio-electric. 
They  depolarize  light,  and  according  to  Dr.  Brewster,  their 
axes  are  perfectly  neuter,  being  parallel  and  perpendicular  to 
the  axes  of  the  hair. 

According  to  Mr.  Hatchett,  a  continued  ebullition  of  the 
hairs,  deprives  them  of  a  little  gelatine,  while  the  remaining 


OF  THE   HAIRS.  233 

substance,  which  loses  a  portion  of  the  elasticity  and  tenacity 
of  the  hair,  has  all  the  properties  of  coagulated  albumen.  They 
strongly  resist  putrefaction.  Their  colour  changes  at  first,  but 
the  corneous  matter  resists  for  a  great  length  of  time.  Vau- 
quelin  has  found  that  they  dissolve  in  Papin's  digester;  that 
they  are  dissolved  by  water  containing  four  hundredths  of 
caustic  potash;  and  that  they  are  acted  on  by  all  the  acids. 
According  to  this  celebrated  chemist,  they  are  composed  of 
an  animal  matter  which  forms  their  base,  of  a  small  quantity 
of  a  white  concrete  oil,  of  a  blackish  oil,  of  iron,  oxide  of  man- 
ganese, phosphate  of  lime,  carbonate  of  lime,  silex  and  sul- 
phur. 

§  341.  They  are  neither  irritable  nor  sensible;  their  force  of 
formation  or  vegetative  power  is  very  active. 

The  motions  of  the  hairs  are  communicated  to  them  by  the 
sub-cutaneous  muscles,  and  by  the  contraction  of  the  skin  itself. 
Each  of  the  large  hairs  or  prickles  of  certain  animals,  are,  in 
addition,  provided  at  the  root  with  a  little  muscle  destined  to 
elevate  it.  Although,  strictly  speaking,  the  stems  of  the  hairs 
are  insensible,  yet  as  their  roots  are  placed  over  a  papilla  pro- 
vided with  a  nerve,  they  transmit  to  it  with  great  accuracy 
the  effects  of  contact  with  external  bodies  that  act  on  them 
mechanically.  Their  production  or  vegetation  is  continual,  it 
is  analogous  to  that  of  the  epidermis  and  the  nails,  and  like  it, 
constitutes  a  true  excretion.  Certain  facts  seem  to  indicate, 
that  there  occurs  in  their  interior,  not  a  true  circulation,  but  an 
imbibition,  and  that  a  coloured  liquid  slowly  traverses  them, 
from  the  root  towards  the  summit.  They  have  been  stated, 
without  any  proof,  to  be  organs  of  absorption.  Their  use  is  to 
protect  the  skin,  and  in  some  places,  particularly,  to  serve  the 
purposes  of  sensation.  They  have  also  local  uses. 

§  342.  The  hairs  present  considerable  differences,  relative 

to  the  regions  they  occupy,  and  have  received  various  names. 

On  the  cranium  they  are  called,  hair,  capilli,  coma,  ctesa* 

ries:  these  hairs  are  the  longest,  the  most  numerous,  strongest 

and  thickly  set. 

The  brows  and  lashes  belong  to  the  eyes;  the  orifices  of  the 
nostrils  and  ears  are  also  furnished  with  hairs. 


234  GENERAL  ANATOMY. 

The  cheeks,  the  environs  of  the  mouth  and  chin  are  occu- 
pied by  the  beard,  barba,julus,  mystax,  pappus. 

The  groin  is  furnished  with  them,  glandebalae,  as  well  as 
the  yubis, pubes,  the  scrotum  labia  pudendi,  and  around  the 
anus. 

The  rest  of  the  body,  both  trunk  and  limbs,  are  more  or  less 
possessed  of  them.  On  the  trunk  they  are  more  numerous  on 
the  anterior  than  the  dorsal  face,  which  is  precisely  the  re- 
verse of  what  generally  takes  place  in  animals;  in  the  limbs 
there  are  fewer  on  the  internal  side  than  the  external  one. 
The  hairs  of  the  greater  part  of  the  body  and  limbs  are  thinly 
scattered,  very  fine,  short,  and  scarcely  visible;  they  have  no 
particular  names,  and  are  in  great  numbers  and  highly  de- 
veloped in  particular  hairy  individuals,  homines  pilosi. 

§343.  The  rudiments  of  the  hairs  are  perceptible  on  the 
foetus  about  the  middle  period  of  pregnancy.  They  make 
their  appearance  in  the  mucous  body  in  form  of  globules  simi- 
lar to  those  of  the  pigment.  On  these  globules  arise  little  hol- 
low cones,  the  sheaths  of  the  hairs.  They  remain  for  some  time 
under  the  epidermis,  and  finally  traverse  it  obliquely,  through 
pores,  it  has  been  said,  but  none  are  to  be  found. 

At  an  early  period,  on  the  skin  of  the  foetus,  is  found  a  fine 
down,  lanugOj  at  first  colourless,  that  covers  the  whole  of  the 
body,  and  which  assumes  in  the  different  regions  determinate 
directions.  These  silky.hairs,  are,  for  the  most  part,  detached 
about  the  eighth  month  of  gestation,  and  are  found  in  the  water 
of  the  amnios,  and  in  the  meconium.  It  is  in  the  last  month 
that  the  eye-brows,  eye-lashes,  and  the  hair  begin  to  appear. 
After  birth  the  remainder  of  the  down  falls.  At  the  age  of 
puberty  begin  to  appear  the  beard,  the  hairs  of  the  nose  and 
ear,  those  of  the  axillas,  the  pubis,  the  organs  of  copulation, 
the  anus,  and  those  of  the  rest  of  the  body.  After  the  adult 
period  of  life,  and  in  old  age,  the  hairs  generally  become  white 
and  fall. 

The  hairs  of  the  head  are  generally  longest,  and  most  numer- 
ous in  females;  they  have,  generally,  no  beard,  nor  hairs  round 
the  anus,  and  those  of  the  remainder  of  the  body  are  finer  and 
more  thinly  scattered.  After  the  age  of  fecundity  the  beard 


OF  TJIE  HAIRS.  235 

is  sometimes  developed.    Women  in  general,  are  less  liable  to 

become  bald  than  men. 
The  human  races,  as  regards  hairs,  present  differences  that 

have  been  already  pointed  out.  (112 — 117.) 

Individuals  also  present  numerous  ones;  some  of  which  re- 
late to  colour,  of  which  there  are  a  great  variety  of  shades; 
others  to  their  thickness,  number  and  length.  Withoff  found 
that  on  a  portion  of  skin  one  fourth  of  an  inch  square,  there 
were  147  black  hairs,  162  chestnut,  and  182  auburn. 

Parts  highly  analogous  to  hairs,  are  found  in  some  of  the 
mammalia  where  they  constitute  spines;  they  are  horny  sheaths, 
coloured^hard,  and  pointed,  and  containing  internally,  a  white 
spongy  substance  that  has  but  little  solidity;  such  are  the  quills 
of  the  porcupine.  The  ordinary  hairs  seem  principally  to  con- 
sist of  the  former  substance. 

§  344.  Accidental  hairs  are  found  on  various  parts  of  the 
skin  and  mucous  membrane,  as  well  as  in  cysts.  A  popular 
error  existed  among  the  ancients  respecting  the  heart,  which 
was  said  to  have  been  covered  with  hair,  accredited  by  Plu- 
tarch and  Pliny.  Homer,  according  to  some,  talks  of  the  hairy 
heart  of  Achilles;  but  it  appears  that  it  is  of  the  hairy  breast 
of  his  hero  that  he  really  speaks.  As  to  the  other  facts,  it 
would  appear,  according  to  the  remark  of  Senac,  that  the  whole 
matter  relates  to  hearts  bristled  with  accidental  cellular  tissue. 
The  accidental  hairs  of  the  skin  are  those  which  are  found  on 
coloured  spots,  or  on  parts  of  the  skin  that  are  thicker  than  the 
rest  of  that  membrane;  they  have  been  known  to  acquire  con- 
siderable development  on  portions  of  skin  previously  inflamed. 
Hairs  have  often  been  seen  growing  from  various  parts  of  the 
mucous  membrane ;  most  generally  they  have  been  found  in 
cavities  lined  by  that  membrane,  or  ejected  either  alone,  or  as 
parts  of  concretions.  Although  many  of  these  facts  are  well 
authenticated,  we  must  not  forget,  that  hairs  may  be  swallowed 
or  otherwise  introduced.  The  hairs  of  the  cysts,  either  cuta- 
neous or  mucous,  are  sometimes  fixed,  and  at  others  free,  and 
in  ordinary  cases  are  mixed  with  fat  or  sebaceous  matter. 
Those  that  are  fixed  in  the  cysts  of  the  ovary,  are  in  general 
very  evidently  placed  on  the  cutaneous  parts  of  those  cysts. 


236  GENERAL  ANATOMY. 

As  to  those  of  the  wens  of  the  eye-brow,  of  the  cranium,  &c. 
they  appear  to  me  to  be  nothing  more  than  sebaceous  folli- 
cles, and  the  hairs  they  contain,  than  hairs  of  the  skin,  which 
instead  of  being  directed  to  the  surface  of  that  membrane 
through  the  orifice  of  the  follicle,  have  been  turned  aside  by 
the  accidental  enlargement  of  that  cavity. 

§  345.  These  alterations  of  the  hairs*  like  those  of  the  nails, 
have  all  their  origin  and  cause  in  the  generating  parts;  the  horny 
part  produced, suffers  its  effects.  When  a  hair  has  been  torn  out 
by  violence  or  has  fallen  by  the  effect  of  a  disease  of  the  skin, 
and  this  has  ceased,  it  grows  again  and  increases  by  the  same 
organic  process  as  the  nails.  This  regeneration  is  effected 
in  the  same  way  as  in  the  first  production  [343.]  When  from 
age  or  other  causes,  the  hairs  begin  to  whiten,  it  is  by  its  free 
extremity  the  albinism  begins;  the  autumnal  whitening  of 
many  animals  takes  place  in  a  similar  mode,  which  seems  de- 
cisively to  indicate,  that  the  interior  of  the  hair  is  the  seat  of 
a  sort  of  imbibition,  the  matter  of  which  is  furnished  by  the 
papillae  of  the  bulb  or  follicle.  This  would  also  seem  to  be 
indicated  by  the  circumstance,  that  after  severe  fevers,  and  in 
many  chronic  diseases,  the  hairs  of  the  head,  when  they  do 
not  fall,  undergo  a  kind  of  diminution  or  atrophy;  they  be- 
come transparent,  dry  and  brittle,  and  when  health  is  restored, 
resume  their  original  qualities.  The  hair  of  the  head  has  also 
been  seen,  after  or  without  experiencing  the  change  produced 
by  albinism,  to  change  colour  and  become  black.  The  mor- 
bid phenomenon  of  the  plica  polonica,  in  which  the  hair  is 
said  to  become  soft  and  fleshy,  and  to  bleed  when  cut  close  to 
the  skin,  forms  no  exception  to  the  general  proposition,  that 
the  stem  of  the  hair  only  participates  in  the  healthy  or  morbid 
state  of  the  skin.  It  may,  in  fact,  easily  be  conceded,  that 
the  papillae  of  the  hair,  if  it  is  inflamed,  may  rise,  contained 
within  the  root  of  the  hair  to  the  level  of  the  skin,  and  that 
its  vascular  tissue  may  be  wounded  in  cutting  the  stem  of  the 
hair,  but  there  is  not  much  exaggeration  in  what  is  related  con- 
cerning this  affection. 

*  Plenck,  de  Morbis  capillorum,  in  op.  tit. — W.  Weclenmcycr,   Hisioria 
pathol.  pilorum.     Getting.  1812,  4to. 


OP  THE  VASCULAR  SYSTEM.  237 


CHAPTER  IV. 


OP  THE  VASCULAR  SYSTEM. 

§  346.  The  vascular  system,  syslema  vasorum,  results  from 
the  union  of  a  multitude  of  ramified  canals,  communicating 
with  each  other,  and  in  which  the  nutritive  fluids  continually 
circulate  throughout  the  whole  body;  receiving  at  the  tegu- 
mentary  sur&ces  the  substances  of  extrinsic  absorption,  and 
there  yielding  those  of  the  excreting  secretion;  alternately 
depositing  in  and  taking  from  the  close  cavities  of  the  serous 
membranes,  and  the  areolae  of  the  cellular  tissue,  continually 
furnishing  the  substance  of  the  organs  with  materials  of  com- 
position, and  constantly  conveying  away  those  of  decompo- 
sition. 

§  347.  In  the  simplest  animals,  the  whole  mass  of  the  body, 
every  way  equally  permeable,  is  directly  imbibed  with  the 
matters  of  absorption,  and  throws  out  in  as  simple  a  manner 
those  of  excretion;  in  animals  placed  a  little  higher  in  the 
scale  of  organization,  the  tegument,  the  essential  seat  of  ab- 
sorption and  extrinsic  secretion,  is  more  or  less  ramified  in 
the  mass  of  the  body,  by  means  of  which  the  substances  for 
absorption  are  distributed,  and  those  of  excretion  drawn  from, 
the  diverse  parts  of  the  jnass  of  the  body;  finally  in  those  of 
a  still  higher  degree,  and  which  embraces  a  great  part  of  the 
animal  kingdom,  we  observe  vessels  penetrating  the  mass  of 
the  body  and  ramified  in  every  direction,  every  way  distri- 
buting and  taking  up  again  the  matter  destined  for  nutrition. 

§  348.  In  man,  as  well  as  in  many  other  animals,  the  blood 
contained  in  the  vessels,  is  continually  conveyed  from  a  cen- 
tral point  to  every  part,  and  returned  from  all  parts  to  the 
centre,  so  as  to  describe  a  circle;  hence  to  this  vascular  system 


238  GENERAL  ANATOMY. 

and  its  dependences  the  name  of  circulatory  apparatus  is  given; 
the  second  name  relating  to  the  formation,  and  the  first  to  the 
function. 

This  system  comprehends  three  species  of  organs,  two  of 
which,  the  arteries  and  the  veins,  contain  blood ;  the  arteries 
convey  it  to  every  part  of  the  body,  and  the  veins  bring  it 
back  from  these  parts;  the  arteries  and  veins  are  united  at  the 
centre  by  means  of  a  hollow  and  muscular  organ,  the  heart. 
The  third  species,  the  lymphatic  vessels,  convey,  not  blood, 
but  chyle  and  lymph,  and  pour  them  into  the  veins;  they 
should  be  considered  as  an  appendage  of  the  venous  system. 

§  349.  The  arteries  and  the  veins  are  in  such  relation  with 
the  heart  and  the  blood,  that  they  may  be  farther  divided  into 
two  other  sections. 

The  blood  is  brought  by  the  veins  from  all  parts  of  the 
body  to  the  heart,  and  hence  conveyed  to  the  lungs  by  the 
pulmonary  artery;  it  returns  from  the  lungs  by  the  pulmona- 
ry veins  to  the  heart,  hence  to  be  conveyed  by  the  aorta  to 
every  part  of  the  body,  from  which  it  is  brought  back  again 
by  the  venae  cavae.  The  name  of  pulmonary,  or  small  circula- 
tion, is  given  to  the  short  circuit  of  the  blood  from  the  heart  to 
the  lungs  and  from  the  lungs  to  the  heart,  and  the  name  of  pul- 
monary vessels  to  the  tubes,  which  give  rise  to  this  circulation. 
The  name  of  general  or  great  circulation  is  given  to  the  course 
of  the  blood  from  the  heart  to  all  parts  of  the  body,  and  from 
these  parts  to  the  heart,  and  the  name  of  aorta  and  of  venae 
cavae,  or  of  general  vessels,  to  those  that  are  traversed  by  the 
blood  in  this  circle. 

§  350.  The  blood  contained  in  the  general  veins  of  the  body, 
in  the  anterior  or  right  side  of  the  heart  and  in  the  pulmonary 
artery,  is  of  a  brownish  red  colour;  it  is  called  venous:  that 
which  is  contained  in  the  pulmonary  veins,  the  other  half  of 
the  heart  and  the  aorta  and  its  branches,  is  of  a  vermilion  or 
arterial  red.  Circulation  has  also  been  divided,  according  to 
the  blood  that  it  contains,  into  that  of  black  blood  and  into 
that  of  red  blood.  Bichat,  author  of  this  division,  which  had 
been  perceived  by  Galen  (sect,  ii.),  has  thought  proper  to 
describe  the  first  mentioned  part  of  the  circulation,  under  the 


OF  THE  VESSELS  IN  GENERAL.  239 

name  of  vascular  system  with  black  blood,  and  that  mentioned 
in  the  second  place,  under  the  name  of  vascular  system  with 
red  blood.  It  is  easy  to  perceive  that  this  division,  pregnant 
with  practical  results,  is  entirely  founded  on  a  physiological 
basis,  and  not  on  the  resemblance  of  the  texture  of  the  parts. 

§  351.  The  three  species  of  vessels  having  a  very  great  ana- 
logy with  each  other;  the  two  sanguineous  vascular  systems 
having  especially  great  relation  with  each  other;  and  the 
venous  and  lymphatic  systems  also  greatly  resembling  each 
other,  we  must,  before  describing  each  species,  present  the  ge- 
neral considerations  just  alluded  to,  those  which  relate  to  the 
vessels  generally,  as  well  as  those  which  refer  to  their  termi- 
nations. 


SECTION  I. 

ARTICLE  I. 
OF  THE  VESSELS  IN  GENERAL. 

§  352.  The  situation  of  the  vessels  is  interior  or  deep  seated. 
The  largest  are  generally  placed  towards  the  centre  of  the 
body,  and  at  the  surface  very  small  ones  only  are  found,  and 
even  in  this  case,  they  are  separated  from  external  bodies  by 
a  layer  of  substance  which  is  not  vascular. 

The  principal  vessels,  either  in  the  trunk  or  in  the  limbs, 
are  generally  placed  in  the  same  directions  as  that  of  the 
flexion  of  the  parts.  We  generally  find  together  an  artery, 
one  or  two  veins,  and  several  lymphatic  vessels:  besides,  we 
meet  with  many  lymphatic  vessels  and  veins  under  the  skin, 
and  but  few  arteries. 

§  353.  The  respective  volume  of  the  three  kinds  of  vessels 
is  such,  generally,  that  the  vessels  which  return  the  fluids, 
that  is  to  say,  the  veins  and  lymphatics,  are,  taken  as  a  whole, 
much  more  voluminous  than  the  arteries.  The  veins  alone 

are  generally  much  more  capacious  than  the  arteries  to  which 
32 


240  GENERAL  ANATOMY. 

they  correspond;  this  holds  good,  particularly  with  respect 
to  the  larger  vessels  of  the  body.  As  to  the  relation  of  volume 
and  number,  or  of  the  total  capacity  between  the  venous  and 
lymphatic  vessels,  it  is  less  known;  it  is  very  well  known, 
however,  that  under  the  skin,  the  mucous  membranes,  and 
around  the  sefous  membranes,  there  are  a  great  many  veins  and 
lymphatic  vessels;  that  in  the  muscular  interstices  of  the  limbs, 
and  of  the  parietes  of  the  trunk,  there  are  also  numerous  lym- 
phatic vessels  with  the  veins,  while  in  the  spinal  canal,  and 
within  the  cranium  there  exists  a  great  many  voluminous 
veins,  and  few  or  perhaps  no  lymphatic  vessels.  Do  these  re- 
lations depend  on  the  difference  of  the  matter  with  which  the 
muscles  and  the  nervous  substance  are  nourished,  and  conse- 
quently on  the  different  matter  which  remains  in  the  circula- 
tion? 

§  354.  The  external  form  of  the  vascular  system  is  that  of  a 
tree,  the  trunk  of  which  is  attached  to  the  heart,  and  which  is 
successively  divided  into  branches,  and  ramusculi  which  be- 
come smaller  and  smaller  branches.  Each  part,  from  its  origin 
in  a  larger  branch  to  its  division  in  smaller  ones,  generally 
preserves  a  cylindrical  form.  Each  branch  being  smaller  than 
the  one  from  which  it  proceeds,  and  larger  than  each  of  the 
ramusculi  arising  from  it,  the  result  is  a  successive  diminu- 
tion from  the  trunk  to  the  end  of  each  of  these  last  ramifica- 
tions. Since,  generally  speaking,  the  sum  of  the  branches  re- 
sulting from  the  division  of  a  trunk,  is  greater  than  the  volume 
of  the  trunk  itself,  it  follows,  that  the  vascular  system  has  the 
form  of  a  cone  whose  summit  is  at  the  heart,  and  whose  base 
is  formed  by  the  union  of  all  the  branches  ramified  in  the  body. 

§  355.  The  number  of  the  divisions  of  the  vascular  system, 
from  its  centre  or  origin,  to  its  last  sub-divisions,  is  not  the 
same  in  all  its  parts.  It  has  been  very  much  exaggerated  in 
computing  it  at  forty;  Haller  was  nearer  to  the  truth,  in  consi- 
dering the  maximum  of  the  successive  divisions  of  a  vessel 
from  its  trunk  to  its  last  ramifications  to  be  about  twenty. 

In  certain  places  vessels  are  divided,  and  form  a  bifurcation 
in  such  a  manner,  that  the  trunk  terminates  by  its  division  into 
two  branches,  and  the  branch,  by  its  separation,  into  two  small 


OF  THE  VESSELS  IN  GENERAL.  241 

twigs.  Thus  the  aorta  bifurcates  and  forms  the  primitive  iliacs, 
these  latter  bifurcate  also  in  their  turn;  the  primitive  carotids 
are  also  divided  into  two  smaller  branches.  The  intestinal 
vessels  present  this  dichotomic  division  in  a  remarkable  man- 
ner. 

The  angles  that  the  vessels  form  in  dividing,  and  at  which 
the  branches  are  separated  from  the  main  trunks,  vary,  but 
the  greater  number  are  acute  towards  their  smaller  branches. 
We  should  observe  with  Haller,  that  these  angles,  to  which 
much  importance  was  formerly  attached,  are  mostly  destroyed 
or  changed  by  dissection,  and  by  removing  the  cellular  tissue 
which  surrounds  the  vessels.  Some  of  the  angles  are  nearly 
right  angles;  these  are  generally  the  first  and  the  largest  divi- 
sions of  the  trunks:  for  instance,  the  branches  of  the  curvature 
of  the  aorta,  the  coeliac,  the  renal  arteries,  &c. ;  the  renal  and 
hepatic  veins,  the  sub-clavian  veins,  the  jugulars,  &c.;  the 
thoracic  duct  at  its  entrance  into  the  left  sub-clavian  vein,  and 
some  others,  such  as  the  median  artery  (sacra  media)  &c. 
Some  vessels  form  even  obtuse  angles,  such  are  the  first  inter- 
costal vessels,  the  inferior  vessels  of  the  cerebellum,  those  of 
the  heart,*  and  some  vessels  of  the  limbs,  &c.  The  greater 
number  finally  form  acute  angles,  and  often  very  acute,  such 
are,  for  instance,  the  spermatic  vessels. 

We  must  observe  with  respect  to  the  angles,  which  are  con- 
sidered as  being  right  angles,  and  even-obtuse,  that  the  greater 
number  are  really  acute;  but  at  a  small  distance  from  the  ori- 
gin, the  branches  after  a  little  distance  change  their  direction, 
bending  their  course  in  contrary  direction  from  that  of  the 
trunk,  resembling  very  much  the  bent  of  the  limbs  of  the 
weeping  willow. 

No  law  or  general  rule  can  be  deduced  from  the  observation 
of  the  angles  formed  by  the  divisions  of  the  vessels.  Thus 
we  observe  the  bifurcations  or  divisions,  and  sub-divisions  of 
the  vessels  of  every  size,  to  form  angles  more  or  less  acute. 

What  is  true  of  the  large  vessels,  is  equally  so  of  the  smallest, 

*  The  coronary  vessels  might,  with  propriety,  have  been  enumerated  first 
among  those  which  form  an  obtuse  angle,  with  the  main  trunk  from  which 
they  arise.  TBANS. 


242  GENERAL  ANATOMY. 

in  the  divisions  of  which  we,  in  like  manner,  generally  find 
acute  angles,  some  right  angles,  and  even  some  obtuse  ones. 

§  356.  The  branches  of  the  different  parts  of  the  vascular 
system,  at  the  same  times  that  they  divide  or  ramify,  in  pro- 
portion as  they  are  removed  from  the  centre  of  the  system, 
nevertheless  conimunicate  or  anastomose  with  each  other.  The 
lymphatic  vessels  are  those  which  have  the  greatest  number  of 
these  communications;  in  the  veins  there  are  a  great  many,  in 
the  arteries  there  are  fewer,  and  nevertheless  they  possess  a 
considerable  number.  These  anastomoses  occur  by  the  union 
of  two  vessels  of  the  same  kind,  and  of  an  equal  volume  or 
calibre. 

In  some  parts,  two  vessels  approach  each  other  obliquely, 
unite  in  a  single  trunk,  which  follows  the  mean  direction  of 
the  two  vessels;  such  is  the  union  of  the  two  vertebral  arteries, 
in  order  to  form  the  basilar  artery,  that  of  the  anterior  spinal 
arteries,  that  of  the  aorta,  and  of  the  pulmonary  artery  in  the 
foetus,  that  of  a  great  many  veins,  &c. 

Generally,  vessels  anastomose  in  such  a  manner  as  to  form 

by  their  union  an  arch,  from  the  convexity  of  which  arise 

many  branches;  this  arrangement  is  observed  in  the  rnesente- 

ric  or  intestinal  vessels,  about  the  articulations,  in  the  hand, 

*  in  the  foot,  &c. 

In  other  places  two  vessels,  each  following  its  direction, 
communicate  by  a  transverse  branch;  such  is,  for  instance,  the 
communication  between  the  umbilical  arteries  in  the  placenta; 
such  are  those  of  the  brain,  of  the  right  with  the  left  side,  and 
of  the  anterior  with  the  posterior  part;  such  are  also  those  of  a 
great  many  veins  and  arteries  of  the  limbs. 

In  several  places,  these  various  and  more  or  less  numerous 
communications  form  circles  or  polygons,  like  the  circle  of 
Willis,  at.  the  base  of  the  brain;  those  of  the  iris  and  mouth, 
that  which  encircles  the  stomach,  &c. 

In  a  great  number  of  parts,  or  almost  every  way,  the  vessels 
which  anastomose  in  an  arch,  uniting  likewise  with  others 
proceeding  from  branches,  some  being  near,  and  others  far- 
ther removed  from  the  centre  of  the  vascular  system,  establish 
collateral  ways  of  circulation:  thus,  for  instance,  the  circum- 


OF  THE  VESSELS  IN  GENERAL.  243 

fiexa  ilii  communicate  at  the  same  time  above  with  the  vessels 
of  the  trunk,  and  below  with  the  vessels  of  the  knee,  and  these 
vessels  at  the  same  time  communicate  also  with  the  branches 
proceeding  from  the  vessels  of  the  leg. 

Generally  the  vessel  or  vessels  which  result  from  an  anasto- 
mosis, are  more  voluminous  than  either  of  the  anastomosing 
vessels  and  less  than  both  united. 

Anastomoses  are  so  much  the  more  frequent  as  they  o.ccur  be- 
tween smaller  vessels  and  in  parts  the  more  distant  from  the 
centre;  they  occur  also  between  larger  branches  in  the  extre- 
mities; for  instance,  in  the  cavity  of  the  cranium,  in  the  hand 
and  in  the  foot.  In  most  cases  they  establish  a  communication 
between  vessels,  whose  origin  is  very  near;  in  some  cases 
they  cause  vessels,  the  origin  of  which  is  pretty  distant,  or 
even  very  distant,  as  for  instance,  from  the  subclavicular  to 
the  inguinal  regions.  The  anastomoses  of  the  sanguineous 
vessels  are  more  numerous  and  larger  around  the  articulation, 
than  in  the  parts  between  them;  those  of  the  veins  and  of  the 
lymphatic  vessels  are  very  frequent  between  the  principal 
trunks;  those  of  the  veins  particularly,  are  much  multiplied 
under  the  skin. 

We  may  form  an  idea  of  the  number  and  importance  of  ana- 
stomoses since  the  aorta*  may  be  narrowed,  obliterated,  even 
tied  without  preventing  the  circulation  or  the  injection  to 
reach  every  part  of  the  body;  that  the  largest  veins,t  even  the 
venae  cavse  being  obliterated,  nevertheless  the  blood  circulates; 
and  that  the  thoracic  ductj  has  been  obliterated  or  tied  with 
impunity. 

Anastomoses  facilitate  and  render  more  uniform  the  circu- 
lation of  the  fluids  of  the  body. 

§  357.  The  larger  vessels  follow  a  pretty  straight  course, 
generally  parallel  to  the  axis  of  the  body;  this  is  the  reason 

*  Scarpa  on  Aneurism. — A.  Cooper  and  B:  Travers'  Surgical  Essays, 
part  i.  Lond.  1818. 

•}•  J.  Hodgson,  Affections  of  the  Arteries  and  Veins. 

t  Flandrin,  Journal  de  Medicine,  torn.  Ixxxvii.  Paris,  1791. — A.  Cooper, 
in  Medical  Records  and  Researches,  &?c.  Loud.  1813. 


244  GENERAL  ANATOMY. 

why  surgeons  prefer  making  their  incisions  in  the  longitudi- 
nal direction,  in  order  to  avoid  wounding  them. 

In  many  places,  however,  vessels  have  a  fluctuating  course. 
The  fluctuation  of  the  vessel  consists  in  a  deviation  or  alter- 
nate undulation  of  the  vessels  from  a  straight  lino;  it  increases 
when  the  vessels  are  turgid,  or  when  a  subject  is  injected,  and 
in  the  arteries  during  the  systole  of  the  heart;  it  diminishes 
under  opposite  circumstances,  and  especially  by  closely  dis- 
secting the  vessels.  In  the  vessels  of  the  parts  subject  to  great 
change  of  volume,  figure  and  situation,  this  fluctuation  is  very 
well  marked;  as  for  instance,  the  mouth,  stomach,  intestine, 
bladder,  uterus,  the  tongue,  and  testicles  before  they  descend 
from  the  abdomen,,  and  those  immediately  surrounding  the  ar- 
ticulations: in  these  latter,  however,  there  is  less  fluctuation, 
but  the  vessels  are  very  elastic. 

The  vessels  of  the  spleen  and  brain,  and  the  spermatic  veins, 
form  also  a  great  many  windings,  although  they  appear  not  to 
be  intended  for  the  same  use. 

The  fluctuations  of  the  sanguineous  vessels  are  more  strong- 
ly marked  than  those  of  the  lymphatic  vessels,  and  those  of 
the  arteries  more  than  those  of  the  veins. 

§  358.  The  symmetrical  distribution  of  the  vessels  is  very 
imperfect.  This  does  not  exist  in  the  central  parts;  they  are 
very  nearly  symmetrical  as  to  their  divisions,  which  belong 
to  symmetrical  parts,  and  have  no  symmetry  in  those  be- 
longing to  parts  which  are  not  symmetrical.  The  arteries, 
the  veins  and  lymphatic  vessels  present  equally  this  disposi- 
tion. In  certain  animals  and  in  the  embryo,  the  vascular 
system  is  more  symmetrical  than  in  the  adult  man.  More- 
over, besides  the  general  want  of  symmetry,  the  vascular 
system  is  also  subject  to  many  irregularities  in  its  distribu- 
tion. 

§  359.  The  parietes  of  the  vessels  adhere  by  their  external 
surface  to  the  mass  of  the  body  in  which  they  are  ramified; 
their  internal  surface  is  smooth,  polished,  humid,  and  in  con- 
tact with  the  circulating  fluids;  it  presents  a  projection  where- 
ever  the  branches  form  acute  angles  with  the  trunks.  The 
thickness  of  the  parietes,  when  compared  with  the  relative 


OP  THE  VESSELS  IN  GENERAL.  245 

volume  of  the  vessel,  increases  from  the  trunk  to  its  ramifica- 
tions. The  cavity  presents  exactly,  as  we  have  already  said 
[354,]  of  the  vessels  themselves,  the  cylindric  form  in  each 
division;  that  of  a  cone  diminishing  in  size  from  the  trunk  to 
one  of  the  last  divisions;  and  that  of  a  cone  increasing  from 
the  trunk  to  all  its  ramifications. 

§  360.  The  texture  of  vessels  is  formed  of  several  layers 
placed  one  over  the  other,  and  more  or  less  distinct. 

The  internal  membrane  is  thin,  whitish,  more  or  less  dia- 
phanous, uniform,  without  any  visible  fibres,  every  way  con- 
tinuous, but  different  in  the  arteries  and  veins.  It  very  much 
resembles  serous  membranes,  and  is  moistened  by  a  liquid, 
the  origin  of  which  is  not  well  known.  It  forms,  according 
to  the  different  kinds  of  vessels,  a  greater  or  smaller  number" 
of  valves  or  duplicatures,  arranged  in  such  a  manner  as  to  per- 
mit the  passage  of  the  fluids  in  the  direction  of  the  circulation, 
and  preventing  their  retrograde  course. 

The  external  coat,  which  must  not  be  confounded  with  the 
cellular  sheath  which  closely  surrounds  the  vessels,  is  thicker 
than  the  internal,  is  fibro-cellular,  and  is  generally  formed 
with  filaments,  which  are  oblique  with  respect  to  the  direction 
of  the  vessel,  and  which  decussate  each  other. 

Between  these  two  membranes,  a  third  which  is  fibrous,  is 
observed,  it  is  distinct  in  all  the  arteries  that  can  be  dissected, 
as  well  as  in  the  larger  veins. 

§  361.  The  external  membrane  of  the  vascular  system,  and 
especially  the  middle  coat  or  membrane  of  the  vessels,  which 
are  provided  with  it,  are  formed  with  a  particular  fibre.  This 
fibre  has  been  named  elastic  fibre,  elastic  fibrous  tissue,  &c. 
although  the  greater  number  of  the  organs  are  elastic  and 
fibrous,  but  because  it  possesses  this  property  in  the  highest 
degree.  Its  elasticity  had  already  been  observed  by  Nicholls, 
J.  Hunter,  and  Ed.  Home;*  some  modern  anatomists  and 
chemists  have  made  it  an  object  of  their  study.t 

It  not  only  forms  the  parietes  of  the  vessels,  but  of  those  of 

*  Croonian,  Lecture  an  Muscular  Motion,  in  Philos.  Trans,  ann.  1795. 
f  H.  Hauff,  de  systeme  telse  elastic^  &c.    Tubing*,  1822.— Chcvreul,  from 
an  unpublished  note. 


246  GENERAL  ANATOMY. 

the  air  vessels  of  the  lungs ;  it  also  lines  some  excretory  ducts; 
it  forms  the  envelope  of  the  cavernous  body  and  that  of  the 
spleen,  and  the  yellow  ligaments  of  the  vertebras;  it  forms 
moreover,  in  various  animals,  the  posterior  cervical  ligament, 
an  abdominal  tunic  to  the  larger  mammiferous  animals,  the 
ligament  which  raises  the  nails  of  the  cat,  that  which  opens 
bivalve  shells;  and  in  the  greater  number  of  the  mammi- 
ferous animals,  it  supplies  the  place  of  the  little  bones  of  the 
tympanum.  But  it  is  especially  in  the  middle  coat  of  the  arte- 
ries, in  the  yellow  ligaments,  and  in  the  ligamentum  nuchae, 
that  its  characters  are  most  evident.  It  exists  under  two 
principal  forms;  that  of  a  canal,  as  in  the  parietes  of  the  arte- 
ries; and  that  of  bundles,  as  in  the  yellow  ligaments. 

This  fibre  is  opaque,  of  a  yellowish  white,  dry,  firm,  al- 
ways arranged  in  parallel  or  very  slightly  oblique  bundles, 
never  crossing  each  other,  nor  united  by  the  celluar  tissue, 
and  very  easy  to  divide.  It  is  extremely  elastic,  and  in  some 
places  it  may  be  stretched  twice  its  length;  and  afterwards  it 
forcibly  recoils  on  itself,  resuming  its  former  condition.  Its 
strength  in  the  living  body  is  less  than  that  of  the  muscular 
tissue,  but  is  stronger  than  the  latter  in  the  cadaver.  In  both 
these  states  it  is  much  less  than  that  of  the  ligamentous  tissue, 
which  it  is  almost  impossible  to  extend.  It  is  more  tenacious 
where  it  exists  in  bundles,  and  more  brittle  in  the  vessels. 

The  elastic  tissue  contains  nearly  one  half  of  its  weight  of 
water;  when  it  has  lost  its  moisture  by  disseccation,  it  acquires 
a  horny  appearance,  a  dark  yellow  colour,  and  becomes  brittle 
and  diaphanous  like  horn.  If  plunged  at  this  time  in  water, 
it  absorbs  with  avidity,  and  assumes  its  weight,  aspect,  and 
former  elasticity.  It  resists  maceration  for  a  long  time,  and 
the  cellular  tissue  does  not  become  apparent  in  its  structure. 
The  action  of  fire  crisps  it  but  little,  and  leaves  behind  very 
little  charcoal.  Decoction  scarcely  crisps  it,  and  extracts  from 
it  a  small  quantity  of  gelatine,  but  never  melts  it,  and  this 
operation  does  not  destroy  its  elasticity.  Acids  render  it 
but  little  horny  and  do  not  make  it  transparent;  it  resists  their 
action  for  a  long  time,  or  experiences  no  effect  at  all.  Diluted 


OP  THE  VESSELS  IN  GENERAL.  347 

alkaline  solutions  do  not  alter  its  form,  and  dissolve  it  very 
little. 

The  greater  number  of  these  anatomical,  physical  or  chemi- 
cal characters,  are  altogether  the  reverse  of  those  of  the  liga- 
mentous  tissue,  and  different  from  those  of  the  muscular  fibre, 
with  which  the  elastic  tissue  has  been  very  improperly  con- 
founded. It  resembles,  however,  in  some  respects,  the  mus- 
cular fibre,  and  seems  to  be  of  a  nature  intermediate  between 
this  latter  and  the  cellular  and  fibrous  tissues. 

Its  vital  properties  are  very  obscure,  especially  in  the  liga- 
ments, and  even  in  the  larger  vessels.  Its  functions  depend  on 
its  elasticity,  which  every  way  antagonises  the  action  of  gravi- 
tation, or  that  of  the  muscles. 

§  362.  The  parietes  of  the  vessels  are  themselves  provided 
with  sanguineous  and  lymphatic  vessels,  vasa  vasorum.  The 
former  may  be  perceived  in  all  the  vessels  which  are  not  less 
than  half  a  line  in  diameter;  but  they  can  not  be  traced  into 
the  thickness  of  the  inner  membrane.  The  lymphatics  can 
only  be  observed  on  the  larger  vessels.  The  vascular  system 
is  also  provided  with  nerves*  furnished  by  the  spinal  marrow, 
and  by  the  great  sympathetic,  and  which  are  distributed  in  the 
external  parts  of  their  parietes. 

§  363.  The  vessels  whose  trunk,  branches,  and  the  principal 
ramifications  are  placed  in  the  common  cellular  tissue,  after 
having  divided,  penetrate  into  the  mass  of  the  organs,  there 
ramify  to  such  an  extent  as  to  become  invisible  to  the  naked 
eye,  and  terminate  as  we  shall  mention  presently;  but  the  dis- 
tention  of  the  vessels  in  the  organs  varies  in  several  points 
which  it  is  necessary  to  treat  of  successively. 

§  364.  Their  origin  is  more  or  less  distant  from  their  termi- 
nation, and  consequently  they  have  various  lengths.  Gene- 
rally, vessels  branch  off  from  their  trunk  very  near  the  organ 
to  which  they  are  destined.  When  this  is  not  the  case,  it  is 
owing  to  some  local  disposition.  Thus  the  spermatic  vessels 
have  their  origin  at  a  great  distance  from  the  organs  in  which 

*  Wrisberg,  de  Nereis  arteries  venasque  cornitantibus;  in  syllog.  comm. 
Getting.  1800. 

33 


248  GENERAL  ANATOMY. 

they  terminate;  because  primitively  the  testicles  and  ovaries 
were  situated  near  the  kidneys. 

§  365.  The  number,  the  volume,  and  consequently  the 
amount  of  vessels,  as  well  as  the  quantity  of  liquid  they  carry, 
vary  equally  in  the  different  organs.  The  greater  number  of 
organs  receive  several  vessels  of  each  kind:  such  are,  for  in- 
stance, the  muscles,  the  bones,  the  encephalon,  the  stomach, 
the  intestines,  the  uterus,  &c. ;  some  have  only  a  single  arte- 
rial and  a  venous  trunk;  such  are  the  spleen,  the  kidneys,  &c. 
The  vessels,  almost  always,  greatly  subdivide  at  the  surface  of 
the  organs  before  penetrating  into  their  interior,  as  is  observed 
in  the  brain,  the  bones,  the  muscles,  &c.;  sometimes  they  enter 
into  an  organ  through  one  single  point,  and  subdivide  within 
its  mass,  such  as,  for  instance,  the  spleen,  the  testicles,  &.c. 

The  amount  of  the  vessels,  resulting  from  their  number,  and 
from  their  volume,  as  well  as  the  quantity  of  the  fluid  con- 
veyed through  them,  vary  greatly.  The  most  vascular  parts 
are  the  lungs,  then  the  tegumentary  membranes,  the  pia-mater 
and  choroid ;  then  the  glands,  the  follicles,  the  vascular  gan- 
glions, the  cortical  substance  of  the  brain,  and  the  nervous 
ganglions;  then  the  muscles,  the  periosteum,  the  adipose  tissue, 
the  medullary  nervous  substance,  the  bones,  and  the  serous 
membranes;  then  the  tendons,  the  ligaments;  finally,  the  carti- 
lages and  the  arachnoid  are  but  little  so  or  not  at  all;  and  the 
epidermis,  the  nails,  the  hair,  the  ivory,  and  the  enamel  of  the 
teeth,  seem  to  be  altogether  deprived  of  vessels.* 

§  366.  Having  arrived  in  the  tissue  of  the  organs,  and  hav- 
ing attained  a  degree  of  tenuity  more  or  less  great,  the  vessels, 
by  their  divisions  and  subdivisions,  by  their  direction,  and  by 
their  anastomoses,  form  a  very  minute  net- work,  the  form  of 
which,  although  very  diversified,  is  always  the  same  in  the  same 
parts.  They  present  arborizations  in  the  intestines  and  epi- 
didymis,  stars  on  the  liver,  tufts  on  the  tongue,  tendrils  in  the 
placenta;  they  have  the  form  of  a  bottle-brush  in  the  spleen, 
resembling  a  bundle  of  rods  in  the  muscles, curls  in  the  testicles 

*  See  Soemmering',  de  Corp.  human,  fabric:!,  V.  iv.  tmgiologia,  1800. — G. 
Prochaska,  Disquisitio  anat.  physiol.  organismi  corp.  hum,  &c.  foennae,  1812. 
Cap.  ix.  De  vosis  scmguintis  capillaribus,  &c. 


OF  THE  VESSELS  IN  GENERAL.  249 

and  in  the  plexus  choroides,  fringes  in  the  pia  mater,  a  trellis  in 
the  pituitary  membrane,  tufts  in  the  crystalline;  they  are  arched 
in  the  iris,  &c.  These  modes  of  formation  are  so  constant  and 
regular,  that  by  examining  with  the  microscope  a  small  por- 
tion of  a  well  injected  organ,  we  may  easily  recognise  to  which 
part  it  belongs.* 

§  367.  The  vessels  are  more  or  less  diaphanous,  according 
to  their  thickness.  They  are  whitish.  Whatever  the  density 
of  their  parietes  may  be,  especially  at  their  inner  surface,  they 
are  permeable  in  the  cadaver,  and  even  in  the  living  body, 
either  from  without  inwards,  or  from  within  outwards.  Their 
tenacity  or  cohesion  is  considerable ;t  but  is  not  the  same  in 
the  three  kinds,  in  everyone  of  their  parts,  nor  in  the  various 
coats  with  which  they  are  composed.  The  same  is  the  case 
with  respect^o  their  elasticity,^:  which  is  generally  con- 
siderable, ancfwhich  exists  either  in  the  fibres  lengthwise,  or 
in  those  encircling  the  vessels.  They  are  evidently  irritable, 
and  their  vital  contractility  is  generally  in  an  inverse  ratio  to 
their  elasticity.  They  are  not  distinctly  sensible.  Their 
power  of  formation  is  very  active. 

§  368.  The  vessels  are  canals  through  which  the  circulating 
humours  continually  pass  and  moisten  every  part  of  the  body; 
they  together  with  the  heart  are  the  organs  or  agents  of  this 
movement,  both  by  their  elasticity  and  by  their  organic  or  vital 
contractility. 

§  369.  The  formation  and  development  of  the  vascular  sys- 
tem, have  been  particularly  observed  in  the  chicken  in  its 
shell,  rather  less  in  the  foetus  of  the  mammiferous  animals,  and 
little  in  the  human  species.  i 

The  veins,  especially  those  of  the  umbilical  vesicle,  are 
formed  before  the  heart  and  arteries.  It  is  uncertain,  if  in  the 
allantoid  or  umbilical  vessels,  the  veins  are  also  formed  before 

*  See  Soemmering  loc  cit, — Prochaska  he  cit. 

j-  Cl.  Wintringham,  experimental  inquiry  on  some  parts  of  the  animal  struc- 
ture; London,  1740. 

$  D.  Hoffman,  Diss.  inaug-  med.  de  elastidtatis  effedibus  in  machind  hu~ 
mana;  1734. 


250  GENERAL  ANATOMY. 

the  arteries.     It  is  very  probable  that  in  the  body  of  the  foetus 
the  arteries  are  formed  before  the  veins. 

The  vessels  are  observed  in  the  thickness  of  the  umbilical 
membrane,  under  the  form  of  small,  rounded  vesicles,  and  se- 
parated from  each  other;  these  vesicles  augment  in  number 
and  unite,  which  produces  a  very  loose  vascular  net-work. 
Their  first  rudiments  are  in  the  beginning  deprived  of  proper 
parietes,  and  consist  in  mere  passages  made  in  the  substance  of 
the  membrane.  This  substance  accumulates  by  degrees  about 
their  circumference,  and  this  forms  their  parietes.  The  tex- 
ture and  composition  of  these  parietes,  are  only  developed  in 
time. 

As  to  the  primitive  simplicity  of  the  circulation  in  the  fce- 
tus,  its  successive  complication,  the  formation  of  the  heart, 
that  of  the  pulmonary  vessels,  &c.  more  particularly  belongs 
to  special  anatomy,  and  especially  to  embryology,*  than  to 
general  anatomy. 

The  number  of  the  vessels  generally  and  their  diameter, 
and  consequently  their  sum  total,  are,  as  relate  to  the  mass  of 
the  body,  so  much  the  more  considerable  as  the  animal  is 
nearer  the  time  of  its  formation.  The  vessels,  in  general, 
especially  the  sanguiferous,  and  more  particularly  the  arteries, 
acquire  considerable  density  in  old  age. 

§  370.  The  circulating  system  presents  little  differences 
relative  to  the  sexes;  nevertheless  the  vessels  are  rather 
thicker  and  firmer  in  the  males.  There  is  no  appreciable  dif- 
ference in  the  races  of  men. 

Individual  varieties,  on  the  contrary,  are  very  frequent  and 
very  numerous  in  this  system;  they  consist  particularly  in 
differences  of  origin,  volume,  number  and  precise  situation; 
they  exist  nearly  in  the  same  degree  in  the  three  species  of 
vessels. 

§  371.  Under  many  circumstances,accidental,and  commonly 
very  minute  vessels,  are  formed. 

Adhesions,  at  first  simply  glutinous,  become  afterwards 
vascular.  The  same  is  the  case  with  respect  to  the  accidental 

*  Ph.  Beclard,  Embryologie  on  Essai  anat.  sur  k  foetus  humain,  in  4to. 
Paris,  1821. 


OF  THE  TERMINATION  OF  THE  VESSELS.  251 

teguments  or  cicatrices.  All  the  accidental  productions  ana- 
logous to  the  organic  tissues,  are  in  the  same  condition. 
The  greater  number  of  morbid  productions,  which  have  no 
analogous  case  in  the  organism,  are,  on  the  contrary,  deprived 
of  vessels.  These  latter  are  formed  in  the  cases  alluded  to  in 
the  same  manner  as  in  the  embryo.  The  mass  in  which  they 
are  formed,  consisting  frequently  in  a  coagulated  liquid,  at  first 
without  vessels,  presents  in  the  beginning  isolated  vesicles,  by 
which  uniting,  form  passages  or  canals  through  the  substance, 
or  without  distinct  arid  proper  parietes;  these  vessels  after- 
wards communicate  with  those  of  the  surrounding  organs; 
they  frequently  remain  for  some  time  more  or  less  different, 
and  not  unfrequently  always  so,  from  the  primitive  natural 
vessels,  either  by  their  manner  of  dividing,  or  particularly  by 
the  absence  or  tenuity  and  softness  of  their  parietes;  in  many 
cases,  on  the  contrary,  the  vessels  acquire  in  time  a  texture 
altogether  similar  to  that  of  the  other  vessels. 

§  372.  Amongst  the  alterations  to  which  the  vessels  are 
subject,  some  are  common  to  the  three  kinds;  such  as  the  di- 
latation and  wounds;  the  others  are  peculiar  to  each  of  them. 
The  former  even  present  very  considerable  differences  in  each 
species,  and  require  to  be  indicated  separately. 


ARTICLE  II. 
OF  THE  TERMINATION  OF  THE  VESSELS. 

§  373.  The  terminations  of  the  vessels,  fines  vasorum,  are 
the  last  ramifications  of  the  arteries  and  the  first  radicles  of 
the  veins  and  of«  the  lymphatic  vessels.  Their  knowledge  is 
a  subject  of  minute  anatomical  investigation,  which  has  most 
exercised  the  patience  of  observers  and  the  imagination  of 
etyologists,  who  expected,  with  some  appearance  of  plausibi- 
lity, to  discover  in  it  the  secret  of  the  greater  number  of  the 
functions  and  of  diseases. 

§  374.  In  almost  every  part  of  the  body,  the  vascular  termi- 
nations are  branches  and  radicles  of  an  extreme  tenuity,  and 
which  can  only  be  observed  by  the  help  of  a  microscope.  In 


252  GENERAL   ANATOMY. 

some  parts,  these  terminations,  and  especially  the  radicles  of 
the  veins,  are  larger,  and  possess  an  erectile  power,  which 
renders  them  susceptible  of  experiencing  a  more  or  less  consi- 
derable expansion.  Finally,  in  some  others,  the  terminations 
of  the  vessels  constitute,  by  their  intermixture,  and  their  com- 
munication, ganglions  or  particular  vascular  enlargements. 

I.    OF  THE  CAPILLARY  VESSELS. 

§  375.  The  capillary  or  microscopic  vessels,*  vasa  capilla- 
ria,  thus  called  in  consequence  of  their  tenuity,  are  much 
finer  than  hairs,  and  can  not  be  perceived  with  the  naked  eye; 
although  the  radicles  of  the  lymphatic  vessels  participate  in 
this  characteristic,  nevertheless,  it  is  especially  the  sanguineous 
capillary  vessels  that  we  shall  treat  of  in  this  place. 

§  376.  The  ancients,  who  were  ignorant  of  the  art  of  inject- 
ing vessels,  and  that  of  magnifying  objects  by  the  help  of  op- 
tical instruments,  were  not  acquainted  with  the  extreme  vessels. 
They  believed  there  was  between  the  last  ramifications  of  the 
arteries  and  the  first  of  the  veins,  an  extravasated,  spongy  and 
sanguineous  substance,  called  parenchyma  by  Erasistratus, 
haimalope  by  Araeteus,  and  of  which  they  believed  the  viscera 
were  especially  formed.  This  opinion,  on  the  termination  of 
the  vessels,  was  adopted  almost  unanimously  by  all  the  ana- 
tomists, till  the  period  of  the  discovery  of  the  circulation  of 
the  blood,  and  since  that  time,  by  a  considerable  number  of 
anatomists  down  to  the  present  day. 

The  injections  of  Ent,t  however,  by  demonstrating  the  di- 
rect passage,  and  without  the  extravasation  of  the  injected  li- 
quid, from  the  arteries  into  the  veins;  the  microscopical  ob- 
servations of  Malpighi,J  and  of  Leuwenhoeck,§  made  on  the 
transparent  parts  of  reptiles,  fishes,  and  even  of  bats,  in  which 
the  blood  is  seen  passing  directly  from  the  arteries  into  the 
veins;  experiments  and  observations,  repeated  since  a  great 

*  Prochaska,  de  vasis  sanguin.  capill.;  in  op.  cil. 

f  Apologia  pro  circulat.  sanguin. ;  in  op.  Leidae,  1687. 

}  De  pulmonibusy  Epist.  ii.  in  oper.  omn. 

§  Exp,  el  contemp*  arcan.  natur.  detect.  Epist.  65,  67,  &c. 


OF  THE  CAPILLARY  VESSELS.  253 

many  times,  must  have  caused,  and  indeed  have  generally 
caused  to  reject  the  supposed  parenchyma  interposed  between 
the  terminations  of  the  arteries  and  veins,  in  rendering  evident 
the  ramifications  which  are  not  visible  to  the  naked  eye,  the 
microscopical  divisions,  and  thus  establishing  a  direct  commu- 
nication between  them. 

Minute  injections  and  microscopical  observations,  soon  led 
anatomists  to  admit,  that  instead  of  the  parenchyma  of  the  an- 
cients, every  thing  is  composed  of  vessels  in  the  body;  an 
opinion  which  yet  divides  all  the  cultivators  of  the  science. 

§  377.  The  sanguineous  capillary  vessels  are  the  last  ramifi- 
cations of  the  arteries,  and  the  first  radicles  of  the  veins,  or 
rather  they  are  intermediate  between  the  arteries  and  veins, 
and,  as  has  been  remarked  in  comparing  them  to  the  portal 
system,  foreign  or  indifferent  to  both.  It  is  in  these  vessels 
that,  insensibly  and  without  any  fixed  point,  the  arteries  are 
converted  into  veins;  of  which  we  may  judge  by  the  succes- 
sive increase  or  diminution  of  the  size  of  the  vessels  in  the  one 
or  the  other  direction,  by  the  direction  in  which  the  successive 
divisions  or  union  are  made,  and  at  the  extremity  of  the  fins 
and  the  tail  of  fishes,  by  the  opposite  direction  of  the  course 
of  the  blood.  However,  the  capillary  vessels  have  been  gene- 
rally described  as  the  last  divisions  of  the  arteries,  rather  than 
the  beginning  of  the  veins.  Whether  this  be  well  founded 
and  depend  upon  the  small  veins  being  larger  than  the  small 
arteries,  acquiring  a  considerable  volume  after  a  few  re- 
unions; or  whether  it  is  because  the  veins,  almost  all  provided 
with  valves,  and  more  difficult  to  inject  than  the  arteries,  have 
been  less  the  object  of  investigation.  These  two  reasons  may 
have  contributed  to  give  more  currency  to  the  opinion  in  ques- 
tion. 

§  378.  All  the  capillary  vessels,  however,  have  not  the  same 
volume.  In  this  respect  three  degrees  of  them  may  be  esta- 
blished, by  taking  as  the  largest  those  which  begin  to  be  in- 
visible to  the  naked  eye,  and  as  the  smallest  those  which  ad- 
mit only  one  single  red  globule  of  blood  at  a  time,  and  the  di- 
ameter of  which,  of  course,  is  not  much  larger  than  the  glo- 
bule itself.  (§  72.) 


254  GENERAL  ANATOMY. 

The  larger  capillary  vessels  experience  several  successive 
divisions  before  they  acquire  a  size  capable  of  admitting  a  sin- 
gle red  globule  of  blood. 

These  capillaries  communicate  together  by  an  infinity  of 
anastomoses  so  as  to  form  a  net-work.  They  constitute  the 
largest  portion  of  the  circulating  circle,  the  capacity  of  the  ar- 
terial system  continually  increasing  from  its  origin  at  the  heart 
to  the  capillary  vessels,  and  that  of  the  venous  system  decreas- 
ing from  the  capillary  vessels  to  the  heart. 

The  circulating  circle  being  double  in  man,  there  are  two 
capillary  systems:  the  one  general,  between  the  terminations 
of  the  aortic  arteries,  and  the  origin  of  the  veins  of  the  body; 
and  the  other  pulmonary*  at  the  extremities  of  the  vessels 
which  bear  this  name.  It  has  been  advanced,  but  without  any 
positive  proof  to  support  the  assertion,  that  the  pulmonary  ca- 
pillary system  is  as  capacious  and  contains  as  much  blood  as 
the  general  capillary  system. 

There  are  in  the  abdomen  two  other  small  capillary  systems; 
one  between  the  mesenteric  arteries  and  veins,  the  other  be- 
tween the  hepatic  extremities  of  the  vena  porta  and  the  origin 
of  the  hepatic  veins. 

§  379.  The  texture  of  the  capillary  vessels  can  not  be  ob- 
served with  the  naked  eye.  These  vessels  have  very  thin  and 
soft  transparent  parietes,  invisible  to  the  naked  eye,  and  slight- 
ly visible  with  the  microscope,  very  little  different  from  the 
substance  of  organs,  and  also  from  the  humours  they  convey. 
They  seem  rather  formed  out  of  the  substance  of  the  organs 
than  provided  with  its  own  parietes.  It  is,  however,  very 
probable  that  the  internal  membrane  of  the  vessels,  at  least,  is 
continuous  without  any  interruption,  from  the  arteries  to  the 
veins. 

In  the  living  body  they  are  only  distinguished  by  the  colour 
and  the  direction  of  the  flow  of  the  blood  which  they  contain, 
and  after  death  by  the  colour  of  the  matter  with  which  they 
are  injected.  They  are  distinguished  from  the  spongy  areolae, 
and  the  accidental  cavities  of  the  cellular  tissue,  by  their  con- 
stant, continuous,  and  regular  course. 

§  380.  Although  the  parietes  of  all  the  vessels  are  permea- 


OF  THE  CAPILLARY  VESSELS.  255 

ble,  nevertheless,  this  property  is  particularly  observable  in 
the  smallest  vessels. 

They  are  very  extensible  and  very  contractile.  Irritability 
increases  while  elasticity  diminishes  in  the  vessels  in  the  same 
degree  as  they  approach  their  termination.  The  capillaries 
are  the  most  irritable.*  Their  contractility  is  produced  either 
by  local  and  direct  agents,  or  by  the  nervous  system. 

§  381.  It  is  in  this  part  of  the  vascular  system  that  the 
most  important  phenomena  of  the  organism  occur,  at  least 
of  the  vegetative  functions.     The  capillary  circulation,  i.  e. 
the  passage  of  the  blood  through  the  vessels  of  this  name, 
is,  of  all  the  parts  of  the  circulation,  that,  which  without  be- 
ing independent  of  the  action  of  the  heart,  is  the  least  under 
its  control.     It  is  the  point  of  the  circle  at  which  the  move- 
ment of  the  blood  is  slowest;  it  is  that  in  which  the  blood, 
divided  in  very  small  streams,  has  the  greatest  number  of 
points  of  contact  with  the  parietes  of  the  vessels,  and  the 
most  influenced  by  the  nervous  action.     The  blood  takes  its 
regular  course  through  the  capillary  system  by  going  directly 
from  the  arteries  to  the  veins;  if  it  meets  an  obstacle,  many 
anastomosing  vessels  are  opened  and  permit  it  to  continue 
its  round.     But  this  system  may  also  be  the  seat  of  conges- 
tions, irritations,  and  constrictions,  which  change  the  ordinary 
course  of  the  liquids.     Thus  the  application   of  warm  fluids, 
for  a  few  minutes,  to  the  lower  extremities  of  a  frog,  produce 
a  dilatation  of  the  capillary  vessels,  a  local  and  partial  stoppage 
of  the  circulation,  a  congestion,  in  a  word,  it  causes  the  tis- 
sues which  were  before  white,  to  become  very  red.  The  same 
thing  occurs,  from  various  causes,  on  the  mammiferous  ani- 
mals and  on  man.     The  application  of  cold  or  of  a  diluted  acid 
produces  entirely  opposite  effects.     Mechanical  or  chemical 
irritation  produces  at  first  the  latter  effect,  and  afterwards,  by 
a  kind  of  attraction,  a  concentric  afflux  of  the  liquids  which,  in 
many  vessels,  are  then  pursuing  a  course  opposite  to  that  of 
the  blood. 

*  Whytt,  Physiological  Essays,  8tc.   Edin.  1761.— H.  Van  den  Bosh,  iiber 
das  Hfusketwermogen  der  Haargefasschen.   Monast.  1786. 
34 


256  GENERAL  ANATOMY. 

The  blood  becomes  nevous  in  the  general  capillary  system, 
and  arterial  in  the  pulmonary  capillary  system. 

§  382.  The  sanguineous  capillary  vessels,  such  as  they  have 
just  been  described,  are  not  equally  abundant,  and  have  not 
the  same  volume  in  all  the  parts  of  the  body.  The  amount 
of  the  vessels  of  each  part  may  be  esteemed  by  the  redness 
that  it  acquires  when  congested  or  inflamed,  as  well  as  when 
it  is  injected :  this  latter  method  is  even  preferable.  The  most 
successful  injections  made,  are  those  of  Ruysch,  Albinus,  Lie- 
berkuhn,  Earth,  Bleuland,  Soemmering,  and  Prochaska. 

The  injections  of  Ruysch,  by  filling  the  most  minute  vessels, 
gave  rise  to  the  opinion  that  the  whole  of  the  solid  substance 
of  the  body  is  vascular.  Ruysch  himself,  however,  acknow- 
ledged, that  there  were  in  the  body  parts  more  or  less  vascu- 
lar, and  others  were  entirely  deprived  of  vessels.  Albinus, 
in  examining  injected  parts  while  yet  fresh,  and  also  when 
dried,  observed  that  even  after  the  most  successful  injections, 
there  remains  always  more  or  less  substance  which  was  not 
reached  by  the  injection,  according  to  the  nature  of  the  parts: 
he  thus  controverted  an  erroneous  opinion,  which  had  espe- 
cially arisen  from  the  examination  of  the  parts  while  dried  or 
macerated,  so  as  to  cause  the  parts  which  can  not  be  injected 
to  disappear,  or  to  be  destroyed. 

Microscopical  observations  and  different  experiments  on 
living  bodies  also  show,  that  there  are  parts  more  or  less  vas- 
cular. Thus,  if  the  mesentery  or  the  webs  of  the  feet  of  a 
living  frog  be  examined  with  the  microscope,  we  shall  see 
that  the  most  minute  capillary  vessels,  those  which  admit  only 
one  globule,  are  separated  by  a  considerable  space,  whilst  in 
the  pulmonary  mucous  membrane  of  the  same  animal  it  would 
be  impossible  to  stick  a  very  fine  needle  without  opening  se- 
veral of  these  vessels;  nor  is  there,  on  the  surface  of  the  skin 
of  a  living  man,  a  point  in  which  a  needle  would  not  produce 
the  same  effect;  while  in  the  ligamentous  parts,  in  the  nervous 
substance,  in  the  cellular  tissue,  &c.  considerable  divisions 
may  be  made  without  causing  a  drop  of  blood  to  issue. 

If  all  the  solid  parts  were  vascular,  and  entirely  vascular, 
there  would  be  no  longer  any  difference  between  them,  all 


OF  THE  CAPILLARY  VESSELS. 

the  organs  would  be  homogeneous;  there  would  be  but  one 
organ.  This  organic  simplicity  is  only  to  be  met  with,  on  the 
contrary,  in  animals  deprived  of  vessels. 

§  383.  The  amount  of  the  sanguineous  capillary  vessels,  and 
their  proportion  with  the  solid  and  non-injectable  substance, 
are  not  less  interesting  than  their  disposition  in  the  several 
parts  of  the  body. 

The  cellular  tissue  can  not  be  injected.  The  epidermis,  the 
horny  parts,  the  hair  and  teeth,  are  not  injectable  at  all.  The 
adipose  lobules  are  surrounded  with  a  very  fine  vascular  net- 
work. Cartilages  experience  no  change  whatever  by  injec- 
tion. 

The  serous  and  synovial  membranes  are  but  slightly  red- 
dened by  injection,  but  the  masses  and  the  fringes  of  adipose 
matter  are  surrounded  with  a  very  beautiful  vascular  net- 
work. The  skin  is  the  most  vascular  part.  The  matter  of 
injection  sometimes  transuded  beyond  the  dermis  into  the 
mucous  layer  or  corpus  mucosum.  The  capillary  vessels  of 
the  skin,  which  are  at  first  of  the  first  and  second  magnitude, 
acquire  the  greatest  degree  of  tenuity  in  penetrating  into  the 
papillaB.  The  recent  skin,  immediately  after  being  injected,  is 
much  more  coloured  at  its  external  surface;  it  appears  equally 
coloured  throughout,  when  the  uninjectable  parts  which  con- 
cealed the  vessels  have  disappeared  in  consequence  of  desic- 
cation. The  cutaneous  and  mucous  follicles  are  furnished 
with  a  very  loose  vascular  net-work.  This  is  also  the  case 
with  the  microscopic  alveoli  of  the  mucous  membrane  of  the 
stomach  and  intestines.  The  papillae  of  the  mucous  membrane, 
like  those  of  the  skin,  are  furnished  with  an  infinite  number 
of  capillary  vessels,  which  is  also  the  case  with  the  villosities, 
at  least  their  adherent  extremity.  The  mucous  membrane, 
in  general,  is  still  more  injectable  than  the  skin,  that  of  the 
lungs,  particularly,  is  so  in  the  highest  degree.  The  mem- 
brane of  the  pituitary  sinuses  is  much  less  so  than  the  rest. 
The  conjunctiva  reddens  moderately,  and  less  by  injection 
than  by  inflammation.  The  mucous  membrane  of  the  excre- 
tory ducts,  and  the  glands  themselves,  are  provided  with  nu- 
merous capillary  vessels. 


258  GENERAL  ANATOMY. 

The  ligamentous  tissue  receives  few  blood  vessels;  the  dura 
mater  is  somewhat  rather  better  provided;  and  the  perioste- 
um is  reddened  a  little  by  injection. 

The  bones  have  but  a  small  number  of  vessels.  The  capil- 
lary vessels  of  the  muscles  are  abundant;  the  smallest,  which 
are  tortuous,  accompany  and  surround  the  muscular  fibres,  fre- 
quently anastomosing. 

The  nervous  system  is  furnished  with  capillary  vessels, 
which  are  more  abundant  in  its  envelopes  and  in  the  cineri- 
tious  substance,  than  in  the  medullary  substance.  The  pia 
mater  and  the  neurilema  generally,  which  differ  in  this  re- 
spect from  the  envelopes  of  many  of  the  viscera,  contain  the 
vessels  until  the  greater  part  of  them  have  acquired  a  capilla- 
ry tenuity.  The  cineritious  matter  of  the  brain  and  the  nerv- 
ous ganglia  possess  a  multitude  of  capillary  vessels  of  all  sizes. 
The  white  matter,  on  the  contrary,  either  of  the  encephalon 
or  nerves,  possesses  only  very  small  capillary  vessels,  and  in  a 
smaller  number. 

§  384.  There  is  therefore  in  the  different  organs,  a  greater 
or  less  proportion  of  a  substance  not  vascular,  or  which  at 
least  can  not  be  shown  to  be  so  by  injections. 

Meyer,*  having  introduced  a  colouring  matter  into  the  blood, 
both  by  absorption  and  by  injection,  concluded,  from  the  differ- 
ent colouring  of  the  parts  of  the  body,  that  there  are  two  kinds 
of  organs,  one  set  composed  for  the  greater  part  of  capillary 
vessels,  viz:  the  cellular  tissue,  the  serous  membrane,  the  te- 
gumentary  membranes,  and  the  fibrous  or  ligamentous  tissue; 
the  other,  more  sparingly  furnished  with  blood  vessels,  and 
formed  of  globules  or  of  an  organic  pulp,  viz:  the  glands,  the 
bones,  the  muscles,  and  the  medullary  nervous  substance 

This  proportion  also  changes  with  age;  at  the  commence- 
ment, at  least  in  the  ovipara,  the  blood  is  seen  and  presents 
currents  before  there  are  solid  parts;  soon  after,  the  walls  of 
the  vessels  are  formed.  The  younger  the  animal,  and  the 
nearer  to  the  foetal  state,  the  greater  is  the  proportion  of  ves- 

•  Memoire  sur  f  absorption  veineuse,  &c.  in  deutches  archiv,  &c.  and  in  the 
Journal  complc'mentairc,  vol.  xi. 


OF  THE  CAPILLARY  VESSKLS. 

sels  over  the  non-injectoble  parts.  In  the  same  degree  as  it 
advances  in  age,  on  the  contrary,  the  proportion  of  non-inject- 
ahle  parts  increases,  and  that  of  the  capillary  vessels  dimi- 
nishes. 

§  385.  Beyond  the  capillary  blood  vessels  of  the.  diameter 
of  a  coloured  globule,  are  there  other  smaller  vessels  which 
afford  a  passage  to  the  colourless  part  of  the  blood?  This  is  a 
question  of  very  difficult  solution. 

Boerhaave,  Vieussens,  Ferrein,  Haller,  Soemmering,  Bichat, 
Chaussier,  and  many  modern  anatomists  and  physiologists, 
admit  serous  vessels  beyond  the  last  blood  vessels,  and  Bleu- 
land  even  thinks  he  has  demonstrated  their  existence. 

On  the  other  hand,  Prochaska,  Mascagni,  Richerand,  and 
several  others,  are  of  opinion  that  there  are  no  vessels  of  this 
kind.  It  is  necessary  to  examine  the  facts  and  reasons  ad- 
duced in  support  ofthe.se  opinions. 

§  386.  Edmund  King  was  one  of  the  first  who  substituted 
for  the  hypothesis  of  the  ancients,  respecting  the  existence  of 
a  parenchyma  in  the  viscera,  that  of  a  purely  vascular  struc- 
ture, which  supposes  that  there  are  serous  vessels;  for  the  last 
capillary  blood  vessels  are  far  from  occupying  or  forming  the 
whole  substance  of  the  tissues. 

Vieussens  and  Boerhaave  especially,  have  admitted  not  only 
one,  but  several  orders  of  decreasing  and  colourless  vessels. 
The  disciples  of  Boerhaave,  Haller,  the  most  celebrated  of 
them,  and  most  of  the  physiologists  up  to  the  present  time, 
have  also  admitted  serous  vessels,  forming  a  continuation  of 
the  arteries  beyond  the  point  at  which  the  veins  begin.  They 
found  their  opinion  upon  the  microscopical  observations  of 
Leuwenhoek,  who  speaks  of  vessels  admitting  only  serous 
globules,  upon  the  phenomena  of  injection,  and  particularly 
on  those  of  inflammations,  which  renders  parts  naturally  white 
and  transparent,  more  or  less  red. 

We  may  add  to  this,  that  red  and  injectable  capillary  ves- 
sels known  in  certain  organs, are  in  so  small  a  proportion  to  the 
non-injectable  substance,  that  it  is  difficult  to  conceive  how 
their  nutrition  could  occur  without  there  existing  circulating 


260  GENERAL  ANATOMY. 

passages,  more  extended  and  more  multiplied,  than  those  of 
the  known  blood  vessels. 

J.  Blenland*  has  added  to  these  reasons  an  anatomical  ex- 
periment, which,  if  it  were  repeated  and  confirmed,  would 
furnish  the  most  powerful  argument  in  favour  of  the  existence 
of  serous  vessels. 

It  is  known  that  the  red  injection,  which  is  fine  and  very 
penetrating,  easily  passes  from  the  arteries  into  the  veins 
through  the  intermediate  capillary  vessels.  It  is  equally  known, 
that  colouring  matter  remains  in  the  capillaries,  even  whilst  its 
vehicle  transudes  and  is  infiltrated  in  the  surrounding  sub- 
stance, where,  from  the  want  of  colour,  it  is  impossible  to  dis- 
cern any  form  or  any  particular  direction  in  the  passages  or 
reservoirs  into  which  the  injection  has  made  its  escape.  Blen- 
land formed  the  idea  of  combining  with  the  red  colouring  mat- 
ter another  white  matter,  which  instead  of  being  pulverulent 
and  suspended  in  the  vehicle,  was  dissolved  in  it.  Having 
pushed  his  injection  into  the  arteries  of  a  part  of  the  intestine, 
of  which  the  vessels  were  previously  filled  with  a  coarser  mat- 
ter and  of  another  colour,  and  having  afterwards  separated  the 
peritoneal  coat  from  the  intestine,  he  observed  in  the  external 
surface  of  that  membrane,  by  the  aid  of  the  microscope,  be- 
sides the  capillary  blood-vessels,  which  were  all  filled  with  red 
matter,  another  order  of  finer  and  white  vessels,  arising  from 
the  smallest  arteries  which  had  admitted  the  red  injection,  and 
entirely  different  from  the  vessels  which  are  filled  by  ordinary 
injection. 

But  what  are  these  white  microscopical  vascula  or  very  minute 
vessels,  seen  but  once,  and  on  a  portion  of  membrane  detached 
from  the  neighbouring  parts?  Are  they  exhalent  arterioles, 
opening  at  the  surface  of  the  peritoneum?  Are  they  serous  ar- 
terioles continuous  with  serous  radicles  of  veins,  and  consti- 
tuting a  serous  capillary  system?  Finally,  are  they  lymphatic 
arterioles,  continuous  with  radicles  of  lymphatic  vessels?  It  is 

*  Experimentum  anatomicum,  quo  arieriohrum  lymphaticarum  existentia 
probabilitcr  adstruitur,  instituturn,  descriptum,  ct  icone  illustratum.  Lugd. 
Bat.  1784,  4to. 


OE  THE  CAPILLARY  VESSELS.  2G1 

almost  impossible  to  solve  these  questions.     Were  they  not 
rather  accidental  passages? 

Those  who  have  since  admitted  the  existence  of  serous  ves- 
sels, appear  to  have  been  ignorant  of  this,  being  the  most  pow- 
erful fact  in  favour  of  their  opinion.  Those  who  have  rejected 
them,  have  also  passed  it  over  in  silence. 

The  opinion  of  Mascagni,  Prochaska,  and  others,  respect- 
ing the  non-existence  of  vessels  finer  than  those  which  give 
passage  to  a  single  coloured  globule  of  blood,  may  be  esta- 
blished, first,  upon  the  circumstance,  that  these  vessels  are 
easily  seen  by  the  aid  of  the  microscope  in  living  animals,  and 
by  no  means  smaller  vessels,  although  the  microscope  gives  so 
large  a  volume  to  the  globules  of  the  blood,  that  it  would  be 
easy  to  distinguish  much  smaller  objects;  secondly,  upon  the 
circumstance  that  the  red  injection,  which  is  very  penetrating, 
does  not  clearly  disclose  any  other  vessels  than  those  which 
are  seen  in  the  living  subject.  If  in  this  case  the  parts  become 
more  red,  especially  after  desiccation,  it  may  be  owing  to  the 
dilatation  of  the  vessels,  and  to  the  disappearance  of  the  inter- 
mediate substance.  If  inflammation  reddens  the  parts  still 
more,  it  is  by  the  dilitation  of  the  existing  vessels,  the  forma- 
tion of  new  ones,  and  the  infiltration  of  blood  between  the  ves- 
sels. As  to  the  whiteness  or  natural  want  of  colour  of  certain 
very  vascular  parts,  as  the  conjunctiva,  it  depends  upon  the 
circumstance,  that  the  capillary  vessels  being  in  these  parts  ex- 
tremely small,  the  colour  of  the  blood  can  not  be  perceived  in 
them. 

§  3S8.  The  question,  therefore,  which  relates  to  the  exist- 
ence of  the  colourless  capillary  or  serous  vessels,  is  very  diffi- 
cult or  impossible  to  answer;  and  when  this  expression  is  used 
in  the  present  work,  it  is  to  designate  capillary  vessels  which, 
whether  they  contain  only  the  serum  of  the  blood,  or  the  blood 
in  its  entire  state,  but  in  series  of  single  globules,  which  pre- 
vents its  colour  from  being  perceived,  are  colourless  in  the  or- 
dinary state.  It  is  more  consistent  however  with  reason  not 
to  admit  the  existence  of  vessels  which  no  one  has  ever  seen. 
§  389.  In  the  double  circle  of  the  circulation,  the  evident 
communication  of  the  arterial  and  venous  trunks  occur  in  the 


262  GENERAL  ANATOMY. 

heart,  and  that  of  the  lymphatic  trunks  with  the  venous  trunks 
near  that  organ,  in  the  subclavian  veins.  But  in  the  points  di- 
ametrically opposite  to  this  double  circle,  in  the  capillary  sys- 
tem, the  communication  is  not  so  obvious.  The  ancients  sup- 
posed that  of  the  arteries  with  the  veins,  but  did  not  believe 
the  communication  to  be  direct.  The  discovery  of  the  circu- 
lation of  the  blood,  while  it  made  this  communication  to  be 
necessarily  admitted,  still  left  its  mode  undecided.  We  have 
already  seen,  that  microscopical  observations  and  injections 
agree  in  demonstrating  this  communication,  and  even  showing 
that  it  is  direct. 

Microscopical  observations  have  demonstrated*  it  in  the 
transparent  parts  of  cold  blooded  oviparous  animals,  in  the  in- 
cubated egg  of  birds,  and  even  in  the  transparent  parts  of 
mammiferous  animals. 

Injection  has  demonstrated  it  in  almost  every  part  of  the 
body  of  man  and  animals,!  either  by  forcing  the  matter  through 
the  arteries,  or  by  pushing  it  through  the  veins  into  parts,  as 
the  intestine,  in  which  the  veins  have  no  valves. 

Some  anatomists  had  even  admitted  arterio-venous  commu- 
nications between  vessels  visible  to  the  naked  eye,  and  of  a  cer- 
tain calibre;  thus  Casserius  represents  them  as  occurring  in  the 
liver,  Riolan  describes  them  as  happening  after  a  cured  aneu- 
rism, Lealis  notices  such  communications  between  the  sper- 
matic arteries  and  veins.  These  are  errors,  that  is  to  say,  ill- 
observed  facts,  which  have  been  contradicted  by  Albinus  and 
Haller. 

The  communications  between  the  arteries  and  veins  are  all 
capillary  and  microscopical,  but  it  appears,  that  in  cold  blooded 
animals  at  least,  there  are  some  which  permit  several  coloured 
globules  to  pass  at  once,  and  others  a  single  one  only. 

The  disposition  of  these  passages  of  communication  has 
been  observed  in  animals.  They  consist,  sometimes,  simply 

*  Malpig-hi,  be.  clt.—  Leuwenhoeck.  be.  cit. — Spallanzani,  ExpsrL  sur  la 
circulation,  page  255. 

f  See  particularly:  Ruysc/t  Thes.  anat. — Winslow,  mem.  de  Facad.  dts 
sciences. — Haller,  de  Fabric^  corp.  human?',  vol.  i. — Mascag-ni.  vas.  lymph.  &fr. 
•prodromo  &c. — Proehaska,  lur.  cit. — Reissessen,  de  structure  pnhnon. 


OF  THE  CAPILLARY  VESSELS.  263 

of  a  change  of  direction  or  a  bending  of  a  minute  artery,  which 
becomes  a  venous  radicle;  at  others  a  capillary  artery  and 
vein  parallel  to  each  other,  also  exchange  communicating  radi- 
cles, at  the  point  where  the  artery  changes  into  a  vein;  again, 
and  frequently,  several  capillary  arteries  terminate  or  are  con- 
tinued into  a  single  capillary  vein.  In  all  cases  the  commu- 
nicatiqn  occurs  in  vessels  of  the  capacity  of  from  one  to  four 
or  five  coloured  globules. 

§  330.  Modern  physiologists  have  recently  raised  doubts 
respecting  the  direct  communication  of  the  arteries  and  veins. 
Doellinger  thinks  that  the  arteries,  at  their  extremity,  cease 
to  have  any  parietes,  and  that  the  blood  flows  uncontined  in 
the  solid  substance  of  the  body,  which  he  calls  mucous;  that 
at  this  point,  one  part  of  the  blood  is  converted  into  mucous 
substance,  and  that  another  part  of  it  continues  its  course 
joined  to  sanguified  mucous  substance,  which  is  set  in  motion 
in  liquid  mass,  and  penetrates  into  the  venous  and  lymphatic 
vessels,  arising  from  the  mucous  substance  as  the  arteries  ter- 
minate in  it. 

Wilbrand  goes  still  farther,  and  admits  a  still  more  com- 
plete metamorphosis  in  the  circulation;  according  to  him  the 
whole  of  the  blood  is  converted  into  organs,  or  into  mucous 
substance  and  into  secreted  fluids,  and  the  organs  becoming 
fluid  in  the  same  degree,  is  converted  again  into  venous  fluid 
and  lymph,  which  continue  the  circulation,  and  also  become 
the  matter  of  excretions. 

According  to  one  of  these  opinions,  a  part,  and  according 
to  the  other,  the  whole  of  the  blood  becomes  solid,  and  like- 
wise a  part  or  the  whole  of  the  organs  is  rendered  fluid  at 
each  round  of  the  circulation.  In  the  one  as  in  the  other,  the 
solid  mass  of  the  body  is  interposed  between  the  terminations 
of  the  arteries  and  the  origin  of  the  veins  and  lymphatics.  They 
both  suppose  that  the  microscopical  inspection  of  living  ani- 
mals and  injections  are  deceitful  means  of  determining  the 
communication  between  the  arteries  and  veins. 

§  391.  The  direct  continuity  of  the  arteries  and  lymphatics 
is  not  so  well  demonstrated  as  that  of  the  veins  and  arteries. 
Many  anatomists,  however,  have  admitted,  with  Bartholin, 
35 


2f>4  GENERAL  ANATOMY. 

the  continuity  of  the  lymphatic  vessels  with  the  capillary  arte- 
ries finer  than  those  which  allow  the  passage  of  the  coloured 
globules  of  the  blood.  Haller,  and  most  of  the  anatomists  who 
have  lived  since  his  time,  admit  no  other  origin  to  the  lympha- 
tic vessels  than  the  tegumentary  membranes.  Some  authors, 
among  whom  is  Mascagni,  in  admitting  that  lymphatic  ves- 
sels likewise  arise  from  the  parietes  of  blood  vessels,  thus  in- 
directly admit  a  communication,  although  they  reject  a  direct 
continuation. 

The  inspection  of  living  animals  discloses  nothing  respect- 
ing this  communication.  Injections  sometimes  pass,  and  even 
frequently,  but  ordinarily  colourless,  from  the  arteries  into 
the  lymphatic  vessels;  which  may  depend  on  the  transuda- 
tion  in  the  cellular  substance,  and  on  the  passage  into  the 
lymphatics,  which  arise  from  it;  or  on  the  passage  of  the  mi- 
nute arteries  into  the  lymphatic  vessels  of  their  parietes  ad- 
mitted by  Mascagni,  as  well  as  upon  a  direct  and  immediate 
communication,  which  consequently  remains  very  doubtful. 

§  392.  The  serous  capillary  vessels  which  have  been  ad- 
mitted beyond  the  capillary  blood  vessels,  much  more  from 
physiological  considerations,  than  from  positive  anatomical 
demonstration,  is  not  the  only  hypothesis  of  this  kind.  Ab- 
sorption and  secretion  being  certain  and  evident  facts,  as  al- 
ready announced  by  the  father  of  medicine,*  many  have  been 
the  researches  in  order  to  find,  by  what  passages  substances 
issue  from  the  vascular  system,  and  by  what  passages  they 
enter  it.  Without  ever  having  seen  them,  they  have  been 
described,  the  one  under  the  name  of  exhalent  or  secretory 
vessels,  the  other  under  that  of  absorbent  or  inhalent  vessels. 

The  exhalent  vessels  have  been  admitted  by  Haller,  Hew- 
son,  Soernmering,  Bichat,  Chaussier,  &c.  as  being  very  simple 
vessels,  appearing  to  be  very  minute  and  short  productions  of 
the  capillary  arteries,  and  diffused  in  the  tegumentary  and 
serous  membranes,  and  the  cellular  tissue. 

Other  anatomists,  such  as  Mascagni,  Prochaska,  and  Riche- 


*  A«A.oy,   »   «)V9»crxf,   «'c  txTrvw,  X.M   s/V-mov  oAcv  TO  rapx.      Epedem.  bib.  vi. 
sect.  vi. 


OF  THE  CAPILLARY  VESSELS.  265 

rand,  admit,  on  the  contrary,  the  opinion  that  it  is  by  laternal 
pores,  organically  arranged,  that  secretion  or  exhalation  oc- 


0 

curs. 


Hunter  had  even  admitted  that  it  was  by  pores  or  inorganic 
interstices  that  secretion  took  place,  precisely  in  the  same 
manner  as  transudation  in  the  dead  body.  Hewson  and  Bi- 
chat  have  controverted  this  opinion. 

The  real  passages,  however,  of  exhalation  or  secretion  are 
entirely  unknown.  All  we  know  on  this  subject,  is  merely 
this,  that  in  the  living  body,  fluids  issue  under  the  form  of 
vapour  from  all  points  of  the  capillary  system;  and  that  seve- 
ral are  observed  in  a  liquid  form,  or  even  more  or  less  con- 
crete; while  in  the  dead  body  fine  injections,  in  passing  from 
the  arteries  into  the  veins,  ooze  out  on  the  surface  of  the  skin 
and  mucous  membrane,  in  the  mucous  and  cutaneous  follicles, 
in  the  excretory  ducts  of  the  glands,  on  the  free  surface  of  the 
serous  membranes,  and  in  the  mucous,  areolar  or  cellular 
substance,  which  constitutes  the  solid  mass  of  the  body;  but 
never,  and  nowhere  are  there  seen  ramuscules  arising  from 
capillary  net-works  and  terminating  by  an  open  extremity. 
The  passages  of  exhalation  or  secretion  are  therefore  un- 
known. It  is  very  probable  that  it  occurs  through  the  solid 
and  porous  substance  of  the  body.  Secretion,  fiawever,  is  an 
organic  or  vital  phenomenon  entirely  different  from  transuda- 
tion in  the  dead  body,  as  is  demonstrated  by  the  difference 
which  the  various  secreted  humours  present,  and  the  differ- 
ences of  quantity  of  these  humours.  The  names  of  exhaling 
or  secreting  vessels  can  only  therefore,  designate  the  unknown 
passages  through  which  the  molicules,  formed  by  the  mat- 
ter of  the  intrinsic  and  extrinsic  secretions,  issue  from  the 
circulation. 

§  393.  Nearly  the  same  may  be  said  respecting  the  passages 
or  mechanism  of  absorption.  The  absorbent  vessels,  accord- 
ing to  the  idea  entertained  of  them,  are  radicles  open  at  one  ex- 
tremity, similar  to  the  puncta  lachrymalia,  and  continuous  at 
the  other,  either  with  the  venous  and  lymphatic  net-work,  or 
with  the  lymphatic  vessels  alone,  or  with  the  veins  alone,  of 
which  they  are  thus  the  origin.  Now,  neither  these  canals 


GENERAL  ANATOMY. 

nor  their  patelous  mouths  have  ever  been  seen.  The  follow- 
ing are  the  opinions  and  facts  known  with  respect  to  this  nice 
point  of  anatomy.  Aselli  has  said,  with  reference  to  the  lac- 
teal or  chyliferous  vessels:  "  ad  intestina  instar  hirudinum 
orificia  horum  vasorum  hiant  spongiosis  capitulis"  Hel- 
vetius  asserts  that  the  intestinal  villosities  have  spongy  orifices. 
Lieberktihn  speaks  of  a  spongy  or  cellular  ampulla.  Hewson 
rejects  the  belief  in  this  ampulla.  Cruikshank  describes  and 
figures  twenty  or  thirty  openings,  each  larger  than  a  globule  of 
blood  at  the  summit  of  each  villosity.  Sheldon  makes  the  vil- 
losities terminate  by  a  spongy  tissue,  and  appears  to  confound 
the  follicles  with  them.  Mascagni  could  see  no  orifices  at  the 
summit  of  the  villosities.  Feller  and  Werner  describe  an  am- 
pulla, and  trace  vessels  into  it.  Bleuland  admits  openings  at 
the  summit  of  the  villosities.  Scemmerring  observes  that  from 
six  to  ten  absorbent  orifices  may  be  seen  in  each  of  them. 
Hedwig  considers  the  ampulla  as  spongy,  and  describes  their 
summit  as  having  one  orifice  or  more,  or  none  Rudolphi  has 
never  seen  any  orifices,  and  those  which  have  been  admitted 
seem  to  him  to  depend  on  optical  illusions.  This  is  quite  suf- 
ficient in  order  to  conclude,  that  the  orifices  which  have  been 
described  do  not  distinctly  exist.  We  must  add,  however, 
that  when  a  very  penetrating  injection  is  thrown  into  the  in- 
testinal veins,  the  matter  in  passing  into  the  arteries,  transudes 
also  at  the  free  surface  of  the  mucous  membrane.  It  is  known 
with  respect  to  the  skin,  that  when  a  lymphatic  vessel  of  that 
membrane  has  been  injected,  if  the  mercury  be  pushed  back 
towards  the  roots  of  the  vessels,  it  at  length  issues  from  its  free 
surface,  as  remarked  by  Haas.  Mascagni  has  made  this  experi- 
ment, and  any  person  may  easily  repeat  it,  on  the  sub-perito- 
neal lymphatic  vessels  of  the  liver.  Finally,  Carlisle  asserts 
that  he  has  seen  orifices  of  lymphatic  vessels  in  a  cell  of  the 
cellular  tissue. 

However  doubtful  and  contradictory  the  facts  may  be,  the 
following  is  the  opinion  generally  admitted,  namely,  that  at 
the  surface  of  the  tegumcntary  and  serous  membranes,  in  the 
areolae  of  the  cellular  tissue,  and  according  to  Mascagni,  at  the 
very  surface  of  the  vessels,  there  are  orifices  of  absorbent  radi- 


OF  THE  CAPILLARY  VESSELS.  267 

cles  leading,  according  to  the  greater  number  of  modern  wri- 
ters, into  the  lymphatic  vessels  only,  but  according  to  the 
anatomists  anterior  to  Haller,and  some  more  modern  than  him, 
into  the  veins  only;  and  according  to  others,  both  into  the  ca- 
pillary blood-vessels  and  lymphatics.  Prochaska  adds  to  this, 
among  the  passages  of  absorption,  the  organic  porosities  of  the 
vessels,  which  would  thus  be,  at  once,  the  passages  of  exhala- 
tion and  inhalation.  Absorption  has  also  been  considered  as 
a  purely  physical  phenomenon,  comparable  to  capillary  attrac- 
tion or  imbibition,  by  adducing  in  support  of  it,  the  absorption 
which  occurs  in  the  dead  body. 

The  fact  is  that  the  passages  of  inhalation  are  unknown. 
They  appear  to  be  like  those  of  exhalation,  the  porosities  of 
the  solid  and  permeable  substance  of  the  body.  Absorption, 
however,  like  secretion,  is  an  organic  and  vital  phenomenon 
altogether  different  from  imbibition  in  the  dead  body,  as  is  de- 
monstrated by  the  selection  of  the  substances  absorbed,  and  by 
the  modifications  which  the  activity  of  absorption  presents  in 
various  cases.  When,  in  this  work,  the  term  absorbents  is 
used,  it  is  to  designate  by  a  single  word  the  unknown  passages 
by  which  foreign  substances  enter,  and  those  by  which  the 
matters  of  the  intrinsic  absorptions  pass  into  the  circulatory 
apparatus.* 

§  394.  Imagination  has  not  stopped  at  the  creation  of  exha- 
lent  and  inhalent  vessels,  of  which  we  have  been  speaking; 
nutritive  vessels  have  been  also  supposed. 

The  following  are  the  principal  opinions  entertained  on  this 
subject.  Boerhaave  and  R.  Vieussens  having  admitted  colour- 
less and  decreasing  vessels,  the  former  conceived  the  body  en- 
tirely constructed  of  vessels,  even  those  parts  which  can  not 
be  injected.  According  to  Boerhaave's  system,  the  smallest 
elementary  fibres  form  minute  membranes,  rolled  upon  them- 
selves, to  constitute  the  smallest  nervous  vessels.  From  these 
smaller  vessels  result  the  vascular  membranes  forming  larger 
vessels,  and  so  on  to  the  largest  ones.  He  also  determined 

*  See  experiments  on  Edosmose  and  Exosmose  in  the  No.  7  of  the  Ameri- 
can Journal  of  Med.  Sciences.  TAAVS. 


268  GENERAL  ANATOMY. 

that  the  smallest  nervous  vessels  contain  an  aqueous  fluid,  serv- 
ing for  feeling,  motion,  and  at  the  same  time  nutrition. 

The  opinion  of  Mascagni  as  to  the  elementary  composition 
and  nutrition  of  the  parts,  does  not  differ  much  from  that  of 
Boerhaave.  According  to  Mascagni,  the  division  of  the  arte- 
ries finishes  at  the  point  where,  or  having  arrived  at  the  tenui- 
ty of  a  red  globule  of  blood,  they  are  converted  into  veins. 
There,  they  are  furnished  with  exhalent  porosities,  as  well  for 
the  secretions  as  for  nutrition.  In  all  parts  there  are  orifices 
of  absorbent  vessels  for  taking  up  and  containing  the  nutritive 
molecules.  The  elementary  parts  consist  of  absorbent  vessels: 
these,  by  their  union,  constitute  the  most  simple  membranes 
and  the  smallest  blood  vessels,  which  form  the  most  com- 
pound membranes. 

In  these  two  hypothesis,  every  thing  is  vascular,  and  nutri- 
tion happens  in  the  vessels;  in  the  first,  in  the  finest  ramifica- 
tions of  the  capillary  arteries,  in  the  second,  in  the  finest  radi- 
cles of  the  absorbents.  In  both,  the  vessels  constitute  the  mass 
of  the  body,  and  are  truly  in  a  continual  state  of  circulation. 

Bichat's  opinion  respecting  the  nutritious  vessels  and  nutri- 
tion, is  somewhat  different.  According  to  this  author,  each 
molecule  of  the  organs  is  in  a  manner  placed  between  two 
patulous  vessels;  the  one  a  nutritive  exhalent  which  had  de- 
posited it,  and  the  other  a  nutritive  absorbent,  destined  to  take 
it  up  again. 

Prochaska,  while  he  admits  the  direct  communication  be- 
tween the  arteries  and  veins,  supposes  that  it  is  by  the  porosi- 
ties of  the  parietes  of  the  vessels  and  the  general  permeability 
of  the  substance  which  forms  the  mass  of  the  body,  that  nutri- 
tion occurs. 

§  395.  Nutrition,  whatever  may  be  its  immediate  channel, 
presents  a  continual  two  fold  motion  of  composition  and  de- 
composition. The  simplest  animals  directly  inhale  and  exhale 
the  materials  of  this  double  phenomenon.  Other  animals,  of 
a  more  complex  organization,  have  a  tegument  more  or  less 
prolonged  into  the  mass  of  the  body,  conveying  there  and 
taking  up  again  the  matters  which  are  added  to  it,  and  those 
which  are  separated  from  it.  Others,  still  more  complex,  have 


OF  THE  ERECTILE  TISSUE.  269. 

other  organs,  vessels,  which  transport  from  the  surfaces  into 
all  parts  of  the  mass,  and  hence  back  to  the  surfaces,  the  mat- 
ters of  absorption  and  secretion.  In  certain  animals  provided 
with  vessels,  among  which  is  man,  their  number  is  so  great, 
that  they  seem  to  occupy  and  form  the  whole  mass  of  the 
body.  But,  besides  the  above  considerations,  which  are  de- 
rived from  analogy,  the  arguments  derived  from  inspection 
also  show  that  the  vessels  only  traverse  the  mass  of  the  body, 
and  do  not  constitute  it.  Observation  also  shows  that,  what- 
ever may  be  the  tenuity  or  softness  of  the  last  capillary  ves- 
sels, the  arteries  and  veins  form  continuous  canals. 

Observation  teaches  us,  that  new  substances  enter  into  the 
vessels,  and  that  others  also  unceasingly  issue  from  them. 
But  this  two-fold  passage  takes  place  in  the  finest  parts  of  the 
vessels,  and  by  paths  invisible  even  with  the  best  optical  in- 
struments; the  substances  themselves  circulate  through  these 
passages  in  a  state  of  division,  in  vapour,  which  eludes  the 
senses,  and  is  imperceptible  with  the  best  microscopes.  This* 
passage,  whether  it  occurs  from  without  inward,  or  from  with- 
in outward,  in  extrinsic  absorptions  and  secretions,  or  whether 
it  takes  place  in  the  closed  cavities  of  the  body,  always  ap- 
pears to  be  performed  through  the  intervention  of  the  solid 
and  permeable  substance  of  the  body;  that  is  to  say,  of  the 
substance  called  cellular,  which,  by  imbibing,  transmits  in- 
wards or  outwards  the  inhaled  or  exhaled  molecules. 

The  same  appears  to  be  the  case  with  respect  to  nutrition. 
The  vessels  deposit  and  take  up  under  the  form  of  vapour, 
and  by  invisible  passages,  in  the  cellular  substance,  the  mole- 
cules of  the  composition  and  decomposition  of  the  organs. 

But  all  these  phenomena,  which  are  apparently  physical,  are 
modified  by  the  organized  and  living  body  in  which  they  oc- 
cur. It  is  especially  to  the  unknown  cause  of  these  pheno- 
mena, that  the  name  of  vital  power  has  been  given,  or  more 
particularly,  that  of  power  of  formation. 

II.    OF  THE  ERECTILE  TISSUE. 

§  396.  The  erectile,  cavernous  or  spongy  tissue,  consists 
of  terminations  of  blood  vessels,  and  especially  of  the  radicles 


270  GENERAL  ANATOMY. 

of  veins,  which,  instead  of  being  capillary,  have  more  width, 
are  very  extensible,  and  are  connected  with  numerous  nervous 
filaments. 

§  397.  This  tissue  was  first  observed  in  the  penis,  where  its 
dimensions  are  very  considerable.  Vesalius*  speaks  of  it  in 
these  terms:  corpora  hcec  (cavernosd)  enata  adeumfere  mo- 
dum,  etc  si  ex  innumeris  arteriarum  venarumque  fasciculis 
qiiam  tenuissimis,  simulque  proxime  implicatis,  retia  quae- 
dam  ejformarentur,  orbiculatim  a  nervea  ilia  membranea- 
que  snbstantia  comprehensa.  Malpighit  appears  to  have 
made  the  same  observation:  sinuum  speciem  in  mammarum 
tubulis  et  in  pene  habemus;  in  his  nonnihil  sanguinis  re- 
peritur,  ita  ut  videantur  venarum  diverticula,  vel  saltern 
ipsarum  appendices.  Hunter^  has  seen  the  same  thing  with 
reference  to  the  spongy  tissue  of  the  urethra;  "  It  is  well  to 
remark,"  says  he,  "that  the  spongy  body  of  the  urethra  and 
glans  penis  are  not  spongy  or  cellular,  but  consist  of  a  plexus 
'of  veins.  This  structure,  he  adds  is  visible  in  the  human  sub- 
ject, but  much  more  distinctly  in  some  animals,  as  the  horse 
&c." 

The  greater  part  of  the  anatomists,  however,  who  have  ex- 
amined the  structure  of  the  penis,  and  among  other  De  Graaf, 
Ruysch,  Duverney,  Boerhaave,  Haller  and  his  disciples,  hav- 
ing mistaken  the  nature  of  the  cavernous  and  spongy  tissues 
of  the  penis,  and  having  considered  them  as  being  loose  and 
elastic  cellular  tissue,  forming  cells,  and  interposed  between 
the  arteries  and  veins,  most  modern  anatomists  have  adopted 
this  error.  Duverny,  Mascagni,  Cuvier,  Tiedemann,  Ribes, 
Moreschi,  Panizza,  Farnese,  &c.,have  made  accurate  observa- 
tions on  the  erectile  tissue  of  the  penis  of  the  elephant,  horse, 
man,  &c.,  as  well  as  on  the  clitoris  of  their  females. 

§  398.  Although  the  erectile  arrangement  of  the  vessels  exist 
in  many  parts  of  the  body,  nevertheless,  there  is  a  certain  num~ 
bes  in  which  it  is  much  more  evident.  These  are  the  corpus 
cavernosum  of  the  penis  and  clitoris,  the  spongy  body  of  the 

*  De  carp'  Hum.  Fabried.  Lib.  v.  cap.  14. 

|  Diss.  Epist.  Varii  Jlrgum.  In  op.  omn.  vol.  ii. 

4  Observations  on  certain  parts  of  the  animal  economy.  4to.  London,  1786. 


OF  THE  ERECTILE  TISSUE.  271 

urethra,  the  nymphro,  the  nipple,  the  papillcc  of  the  tcgumen- 
tary  membranes,  &c. 

§  399.  The  erectile  tissue  is  of  very  large  dimensions  in  the 
organs  of  copulation.  Though  it  does  not  present  the  same  de- 
velopment in  the  papillae,  yet  it  may  be  very  distinctly  ob- 
served in  them. 

The  papillae,  those  of  the  tongue  in  particular,  consist  of  en- 
larged soft  nervous  filaments,  destitute  of  neurilema,  inter- 
mingled with  an  innumerable  multitude  of  capillary  blood- 
vessels, tortuous,  arched,  and  anastomosing  with  each  other, 
the  whole  enveloped  and  collected  together  by  a  soft  and  mu- 
cous cellular  tissue.  In  a  state  of  rest  these  papillae  are  small, 
soft,  pale,  and  indistinct.  In  that  of  erection,  on  the  contrary, 
they  are  enlarged,  raised  up,  of  a  red  colour,  swollen  with 
blood,  and  possessed  of  great  sensibility. 

The  nipple  or  the  papilla  of  the  mamma3,  appears  to  differ 
from  the  others  only  in  being  of  larger  dimensions.     The  skin 
and  mucous  membrane  present  the  papillary  and  erectile  dis- 
positions  in   various  degrees,  in   their  whole   extent.     The 
volume  of  the  nerves  and  the  quantity  of  the  blood-vessels, 
are  every  where  proportionate  to  the  degree  of  sensibility. 
The  skin  of  the  pulp  of  the  fingers,  which  is  very  vascular  and 
nervous,  experiences  a  degree  of  swelling,  and  of  manifest  red- 
ness during  the  act  of  touching,  proportionate  to  its  perfection. 
§  400.  The  erectile  tissue  of  the  organs  of  copulation  differs 
from  that  of  the  papillae  only  in  having  its  dimensions  much 
larger.     That  of  the  corpus  cavernosum  of  the  penis  presents 
the  following  disposition.    It  is  enveloped  by  a  sheath  of  elas- 
tic fibrous  tissue,  which  sends  prolongations  into  its  interior. 
The  two  dorsal  arteries  of  the  penis  are  accompanied  by  an 
azygos  vein  forming  a  plexus,  and  by  nerves  of  great  size. 
The  arteries  send  into  the  interior  numerous  minute  branches 
accompanied  by  nerves,  and  the  veins  receive  numerous  radi- 
cles through  the  sheath.     The  interior  is  composed  of  arterial 
ramifications  coming  from  the  dor§al  arteries,  and  central  ar- 
teries, and  of  very  numerous  large  veins,  intermingled  in  all 
directions,  and  anastomosing  a  multitude  of  times  with  each 

other.     These  branches  of  veins  present  dilatations  and  wide 
36 


272  GENERAL  ANATOMY 

communications.  When  one  of  the  arteries  of  the  penis  is  in- 
jected, the  injection,  if  very  fine  and  penetrating,  after  filling 
the  arterial  ramifications,  and  the  internal  venous  plexus,  which 
constitutes  the  corpus  cavernosum,  and  thus  producing  erec- 
tion, returns  by  the  dorsal  vein.  The  corpus  cavernosum  is 
still  more  easily  filled  by  injecting  through  the  vein.  Thus 
the  pretended  cells  of  the  corpus  cavernosum,  are  merely  very 
large  roots  of  veins  forming  a  complicated  plexus,  and  anasto- 
mosing like  capillary  vessels. 

The  erectile  tissue  of  the  urethra  and  glans  have  the  same 
disposition;  the  same  is  the  case  with  respect  to  that  of  the 
clitoris  and  nymphae. 

Erection,  in  the  organs  of  copulation  as  in  the  papillae,  is 
produced  by  the  repletion  of  the  erectile  vessels.  This  reple- 
tion may  depend  on  the  afflux  of  arterial  blood,  which  is  ac- 
companied by  an  exaltation  of  the  sensibility,  and  the  reten- 
tion of  the  venous  blood,  or  by  both  causes  united. 

§401.  There  is  still  a  part  whose  texture  and  phenomena 
greatly  resemble  those  of  the  erectile  organs:  this  is  the  spleen, 
which,  by  this  means,  seems  to  be  a  diverticulum  of  the  blood. 
If  the  spleen  be  exposed  in  a  living  animal,  and  the  course  of 
the  blood  in  the  splenic  vein  be  arrested  by  pressure,  this  or- 
gan swells  and  greatly  augments  in  size;  but  it  quickly  assumes 
its  natural  appearance  as  soon  as  the  circulation  is  re-establish- 
ed. The  accessions  of  intermittent  fever  are  accompanied, 
during  the  chill,  by  a  manifest  swelling  of  this  organ,  which  is 
more  or  less  completely  dissipated  when  the  accession  is  at  an 
end.  It  would  appear  that  the  same  thing  takes  place  during 
digestion. 

§  402.  The  erectile  tissue  is  sometimesaccidentally  developed 
in  the  organism.  This  production  has  been  described  under 
the  names  of  varicose  tumour,  aneurism  by  anastomosis,  aneu- 
rism of  the  smaller  arteries,  telangiectasis,  &c. 

Its  anatomical  characters  are  precisely  the  same  as  those  of 
the  natural  erectile  tissue.  It  is  a  more  or  less  voluminous,  or 
more  or  less  circumscribed  mass,  sometimes  surrounded  by  a 
thin  fibrous  envelope,  presenting  internally  an  appearance  of 
cells  or  spongy  cavities;  consisting  in  reality  of  an  inextricable 


OF  THE  VASCULAR  GANGLIA. 

net-work  of  arteries  and  veins,  which  communicate  by  innu- 
merable anastomoses,  like  the  capillary  vessels,  but  much 
wider,  especially  the  veins,  easily  injectable  by  the  neighbour- 
ing veins,  which  are  sometimes  varicose,  but  with  difficulty 
by  the  arteries. 

This  alteration  most  commonly  exists  in  the  substance  of 
the  skin,  and  to  a  greater  or  less  extent.  It  then  sometimes 
resembles  the  crest  and  other  similar  parts  of  the  gallinaceous 
birds.  The  skin  of  the  face,  and  especially  that  of  the  lips,  is 
frequently  the  seat  of  this  alteration.  It  is  observed  in  the 
subcutaneous  cellular  tissue,  or  more  or  less  deep;  it  has  been 
seen  occupying  a  whole  member;  it  is  even  asserted  to  have 
been  observed  in  some  viscera. 

This  production  is  the  seat  of  a  vibration,  a  rustling,  and  a 
pulsation,  more  or  less  manifest,  and  which  are  increased  by 
all  the  causes  which  excite  the  activity  of  the  general  circula- 
tion; but  the  tumours  which  it  forms,  even  in  the  skin,  are  by 
no  means  susceptible  of  a  kind  of  isolated  erection.  U  is  most 
commonly  congenital,  and  at  other  times  appears  to  depend 
on  an  accidental  cause;  it  sometimes  continues  without  change, 
at  others,  which  is  the  most  common  case,  it  augments  contin- 
ually in  size  by  the  dilatation  of  its  internal  cavities,  and  at 
length  bursts,  giving  rise  to  haemorrhages,  which  are  difficult 
to  repress. 

Around  the  arms  there  occur  hemorrhoidal  tumours,  resem- 
bling the  spleen  in  appearance,  which  constitute  a  variety  of 
this  accidental  erectile  tissue. 

III.    OF  THE  VASCULAR  GANGLIA. 

§403.  The  vascular  ganglia,  adenoid  or  glandiform  organs, 
or  aporic  glands,*  confounded  under  the  common  name  of 
glands  with  organs  of  excretory  secretion,  are  also  parts  in 

*  Queitschius,  De  glandulls  coeds,  &c.  in  select,  med.  Franco/. — Hendy, 
Essay  on  glandular  secretion. — Hewson,  Descriptio  glandul.  SJc.  opus  posthum . 
in  op.  omn. — H.  F.  F.  Leonhardi,  De  glandulis  in  genere  et  glandulis  apori- 
cist  &fc.— Dresden,  1813. 


274  GENERAL  ANATOMY. 

which  the  termination  and  communications  of  the  vessels 
aflfect  particular  dispositions.  Hensinger  has  given  to  them 
the  name  of  parenchymatous  tissue. 

Their  texture  results  from  the  union  of  several  other  tissues. 
They  are  formed  of  modified  cellular  tissue,  of  blood  vessels 
and  lymphatics,  and  of  nerves;  the  whole  inclosed  in  an  enve- 
lope, which  send  prolongations  into  the  interior.  They  are 
all  situated  in  the  course  of  the  lymphatic  and  venous  circu- 
lation, and  seem  to  be  destined  to  make  the  absorbed  sub- 
stances undergo  an  elaboration,  and  to  prepare  their  assimila- 
tion; they  thus  appear  to  be  in  a  kind  of  antagonism  to  the 
true  glands  or  the  organs  of  excretion.  The  vascular  ganglia 
differ  from  each  other  in  the  quantity  and  the  species  of  tissue 
of  which  their  mass  is  formed,  in  the  proportion  of  vessels 
and  nerves,  and  in  the  mode  of  communication  of  the  vessels. 

§  404.  The  adenoid  ganglia  may  be  distinguished  into  two 
kinds:  1st,  the  lymphatic  glands  or  ganglia;  and  2dly,  the 
ganglia  of  the  blood  vessels,  which  are  the  thyroid  gland,  the 
thymus,  the  surrenal  capsules,  and  the  spleen. 

The  former  of  these  will  be  described  along  with  the  lym- 
phatic vessels,  (sect,  iv.)  The  others,  which  form  a  less  na- 
tural group,  belong  principally  to  special  anatomy.  They  have, 
however,  some  general  characters.  The  ganglions  of  the 
blood  vessels*  are  larger  and  much  less  numerous  than  the 
lymphatic  ganglia.  They  are  of  a  brownish-red  colour,  glo- 
bular and  granular.  They  present  internally  distinct  cavities, 
filled  with  a  fluid,  but  little  ramified  and  closed  on  all  sides. 
It  was  believed,  at  divers  epochs,  that  excretory  ducts  had 
been  discovered  in  them,  but  these  supposed  discoveries  have 
not  been  confirmed.  These  ganglia  are  so  intimately  con- 
nected with  the  blood  vessels  and  lymphatics,  and  especially 
with  the  thoracic  duct,  that  they  have  been  supposed,  with 

*  Boeckler,  de  Functionibus  glanduhs  thyreoidx,  thymi,  atque  glandul 
9upraren.t  fcfc.  Argentor.  1753.—  Hecker,  iiber  die  verrichtung  der  kleinsten 
scklagaden  und  einger  cms  einem  gewebe  der  feinsten  gefasse  bestehenden  ein- 
geweide,  der  schild-und  brust-druse,  der  milzes,  der  nebennieren  und  nachge- 
burt,  Erfurt,  1790. 


OP  THE  ARTERIES.  275 

much  probability,  to  have  a  very  great  influence  upon  the  per- 
fecting of  the  lymph  and  chyle,  and  on  the  formation  of  the 
blood. 


SECTION  II. 

OP  THE  ARTERIES. 

§  405.  The  arteries,*  qrteriae,  are  the  vessels  which  convey 
the  blood  from  the  heart  to  all  the  parts  of  the  body. 

§  406.  Hippocrates  and  his  contemporaries  gave  the  name 
of  veins  to  all  the  vessels  and  canals,  with  the  exception  of 
the  trachea,  which  they  called  artery.  Aristotle  is  the  first 
who  speaks  of  the  aorta,  which  he  names  the  small  vein. 
Praxagoras  gives  the  name  of  artery  to  the  aorta  and  its 
branches,  which  he  believed  to  contain  a  vapour.  The  school 
of  Alexandria  distinguishes  the  arteries  from  the  veins  by  the 
thickness  of  the  walls,  and  admits  that  the  blood  may,  under 
certain  circumstances,  pass  into  the  arteries.  Galen,  the 
greatest  anatomist  of  antiquity,  tries  to  prove  that  the  arteries 
are  full  of  blood  in  their  natural  state.  He  considers  the  ve- 
nous system  and  the  arterial  system  each  a  tree,  whose  roots, 
implanted  in  the  lungs,  and  whose  branches,  distributed 
throughout  the  body,  meet  at  the  heart.  It  was  not  until  Ve- 
salius,  that  the  first  rudiments  of  the  art  of  injecting  the  blood 
vessels  were  known,  and  it  was  not  until  his  day  that  some 
notions  respecting  the  texture  of  the  blood  vessels  are  to  be 
found.  Their  functions  and  alterations  have  only  been  known 
in  later  times. 

§  407.  There  are  two  arterial  trunks;  the  aorta  and  the  pul- 
monary artery,  both  have  an  arborescent  disposition,  and  pre- 

*  BassueJ,  nouvel  aspect  de  Pinterieur  des  arteres,  et  de  leur  structure  par 
rapport  au  cours  du  sang;  m£m.  pretcnt.  de  math,  et  de  phys.  torn.  I.  ann. 
1750. — D.  Belmas,  structure  des  arteres,  leurs  proprittts,  kurs  functions  et 
kurs  alterations  organiques.  in  4to.  Strasbourg,  1822. — Ch.  H.  Ehrmann, 
the  same  title,  place  and  date. 


276  GENERAL  ANATOMY. 

sent  an  origin,  a  trunk,  branches,  twigs,  and  ramusculi,  be- 
coming smaller  and  smaller  until  they  reach  their  termina- 
tion. 

Each  of  the  arterial  trunks  arises  from  a  ventricle  of  the  heart, 
and  does  not  present  here  a  continuation  of  the  substance  of 
the  heart,  as  has  even  recently  been  advanced,  but  an  intimate 
and  very  remarkable'  connexion  of  the  middle  membrane  of 
the  artery  is  divided  into  three  festoons,  bordered  with  liga- 
mentous  tissue,  the  orifice  of  the  ventricle  is  furnished  with  a 
ring  of  the  same  tissue,  the  extremity  of  the  festoons  of  the 
artery  is  firmly  fixed  to  the  orifice  of  the  ventricle,  and  the 
triangular  intervals  of  the  dentations  are  likewise  occupied  by 
ligamentous  membranes;  the  internal  membrane  of  the  vessel 
is  continuous  with  that  of  the  heart,  and  the  external  mem- 
brane is  united  to  the  substance  of  that  organ. 

The  trunks,  the  branches  and  all  the  divisions  of  the  arteries 
are  obviously  cylindrical.  There  are  nevertheless  exceptions; 
some  arteries  enlarge  as  they  advance,  while  others  seem  to 
contract.  The  arterial  cylinders  gradually  diminish  from  the 
trunks  even  to  the  last  ramifications. 

Generally  the  sum  of  the  calibre  of  the  branches  is  greater 
than  their  main  trunk,  but  to  this  there  are  exceptions;  thus 
it  is  not  evident,  that  the  carotid  and  brachial  arteries  have 
together  a  greater  capacity  than  the  trunk  of  the  innominata; 
neither  is  it  certain,  that  the  radial  and  cubital  arteries  united, 
have  a  greater  capacity  than  the  brachial.  We  must  not  con- 
found, in  this  comparison,  the  external  diameter  with  the  ca- 
pacity. Besides  it  very  often  happens,  that  the  capacity  of 
the  arterial  branches  changes,  without  an  appreciable  change 
in  their  size;  and  to  cite  only  an  obvious  example  of  it,  the 
uterine  arteries  augment  considerably  during  pregnancy,  while 
the  hypogastric  artery  which  furnishes  them,  increases  but 
little,  and  the  primitive  iliac  artery  not  in  an  appreciable 
manner. 

The  variable  number  of  the  successive  divisions  of  the  arte- 
ries, their  mode  of  division,  and  the  angles  which  are  found 
between  the  branches  and  the  trunks,  have  been  indicated 
[354,  &c.]  as  well  as  the  anastomoses  and  the  lateral  passages 


OP  THE  ARTERIES.  277 

that  they  present  to  the  circulation.     The  same  is  the  case 
with  their  flexuosities. 

The  termination  of  the  arteries,  when  they  become  capillary 
and  microscopic,  occurs  by  their  being  continued  into  veins, 
either  by  red  capillary  communications,  or  by  communications 
of  colourless  vessels  in  consequence  of  their  extreme  minute- 
ness. 

§408.  The  arteries  are  cylindrical  when  examined  inter- 
nally, their  section  is  circular,  excepting  in  the  largest  arte- 
ries, which,  when  empty,  are  slightly  depressed,  and  present 
an  elliptic  section. 

Each  of  the  two  arterial  trunks  is  furnished  with  three  valves 
at  its  origin  in  the  heart.  These  semi-lunar  valves  are  attached 
by  their  convex  edge  to  the  contour  of  the  festoons  of  the  ar- 
tery; their  free  margin  is  straight  and  somewhat  thick,  espe- 
cially at  the  middle,  which  present  a  small  enlargement.  One 
face  is  turned  toward  the  parietes  of  the  artery,  and  the  other 
towards  the  axis  of  the  vessel.  These  valves  are  formed  by  the 
inner  membrane  of  the  arteries,  doubled  on  itself,  and  contain- 
ing in  its  substance  a  thin  layerof  ligamcntous  or  fibrous  tissue; 
their  free  margin  contains  a  small  cord  of  this  tissue,  and  its 
middle  a  fibro-cartilaginous  point.  When  these  valves  fall,  the 
face,  which  corresponds  to  the  ventricle,  becomes  convex,  and 
the  other,  which  corresponds  to  the  canal,  becomes  concave; 
their  free  edges  meet,  touch  each  other,  and  they  exactly  close 
the  vessel.  In  all  the  rest  of  their  extent  the  arteries  are  de- 
prived of  valves. 

The  internal  surface  is  smooth,  polished,  and  moistened. 
The  external  surface  corresponds  to  the  common  and  particular 
cellular  tissue  in  which  the  arteries  ramify.  The  cellular  tissue 
moulded  around  them,  or  separated  by  their  presence,  forms  a 
cellular  sheath  for  them.  This  sheath  is  confounded  externally 
with  the  rest  of  the  cellular  tissue,  or  with  the  substance  of  the 
organs;  internally  it  is  united  to  the  artery  in  so  loose  a  man- 
ner, as  to  permit  the  latter  to  slide  easily  in  its  interior  during 
the  different  motions,  and  to  retire  within  it  by  contracting  in 
the  longitudinal  direction  when  it  is  divided.  This  sheath  is 
pretty  firm  around  the  arteries  of  the  limbs;  in  the  thorax  and 


27$  GENERAL  ANATOMY. 

abdomen  the  sheath  of  the  arteries  is  in  part  formed  by  the 
serous  membranes.  That  of  the  spermatic  arteries  is  remarka- 
ble for  its  looseness,  and  that  of  the  arteries  of  the  brain  is  not 
distinct.  This  part  of  the  anatomy  of  the  arteries,  deserves 
particular  consideration  in  pathology,  and  in  performing  opera- 
tions. 

§  409.  The  texture  of  the  arteries*  results  from  several  su- 
per-imposed membranous  layers.  There  has  been  much  di- 
versity of  opinion  with  reference  to  their  number,  it  being  sup- 
posed to  be,  even  as  far  as  five  by  some  anatomists,  and  re- 
duced to  one  by  others.  It  may  be  fixed  at  three,  namely: 
an  outer,  a  middle,  and  an  inner. 

§410.  The  external  membrane,  called  also,  cellular,  ner- 
vous, fibrous,  &c. ,  is  thin,  and  of  a  whitish  colour,  and  formed 
of  oblique  and  crossed  fibres,  interlaced  diagonally  with  refer- 
ence to  the  length  of  the  vessel.  Externally  this  tissue  is  ra- 
ther loose,  and  adheres  to  the  sheath;  internally,  on  the  con- 
trary, the  little  fibres  are  so  close  that  they  can  only  be  per- 
ceived on  tearing  them  asunder.  In  the  arterial  trunks,  this 
two-fold  disposition  is  so  distinct,  that  the  outer  layer  really 
appears  double;  in  the  middle  sized  and  small  arteries,  on  the 
contrary,  this  layer  becomes  uniformly  close  and  distinct  from 
the  cellular  tissue  of  the  sheath,  and  then  greatly  resembles 
the  ligamentous  tissue. 

This  membrane  is  very  tough  and  very  elastic,  both  in  its 
longitudinal  and  circular  direction.  Supple  and  possessing 
great  strength  at  the  same  time,  it  is  not  divided  by  the  action 
of  ligatures,  even  when  directly  applied  to  it.  When  we  at- 
tempt to  tear  it,  great  difficulty  is  experienced,  and  the  texture 
of  its  oblique  fibres  is  perceived,  which  render  its  tenacity 
equal  in  all  directions. 

§411.  The  middle  membrane,  called  also  muscular,  ten- 

*  Ludwig1,  de  Jlrteriarum  titnicis,  Lips.  1739. — Albinus,  acad.  annot.  lib.  iv. 
Cap.  viii.  de  arterisR  membranis  et  vasis. — A.  Monro,  Remarks  on  the  coats  of 
arteries,  their  diseases,  &fc.,  in  his  works- — Delasone,  sur  la  structure  des  arte- 
res,  mtm.  de  Facad.  des  sci.  1756. — C.  Mondini,  de  JLrteriarum  tunicis,  in 
opusculis  sdeniifici  t.  i.  Bologna,  1817. — A.  Beclard,  sur  les  Blcssures  des 
cu'teries,  Mt'm.  de  la  sod.  mcd.  d1  emulation,  t.  viii.  Paris,  1817. 


OF  THE  ARTKRIES.  279 

dinous,  proper  membrane,  &c.  is  thick  amKof  a  yellowish  co- 
lour, and  is  formed  of  nearly  circular  or  annular  fibres.  This 
membrane,  the  thickest  of  the  three,  is  very  apparent  in  the 
trunks;  it  augments  proportionally  in  thickness,  as  the  arte- 
ries diminish  in  volume.  Its  thickness  is  inconsiderable  in 
the  arteries  of  certain  viscera,  and  particularly  in  the  arteries 
of  the  brain.  It  can  be  divided  into  several  layers  by  dissec- 
tion; this,  probably,  has  led  into  error  those  who  have  ad- 
mitted more  than  three  arterial  membranes.  The  external 
fibres  are  less  close,  the  deeper  seated  still  more  so,  and  thus 
progressively.  These  fibres  do  not  all  encircle  the  vessel. 
The  longitudinal  and  spiral  fibres  which  have  been  admitted 
in  the  middle  membrane,  do  not  exist.  In  the  places  where 
the  arteries  divide,  the  circular  fibres  of  the  trunk  separate 
and  form  on  each  side  a  half  ring,  and  the  annular  fibres  of 
the  branches  succeed  these  latter.  The  middle  membrane  is 
intimately  united  to  the  outer  one. 

The  middle  membrane  has  so  great  a  degree  of  strength, 
that  when  detached  from  the  others  it  retains  its  cylindrical 
form;  it  is  to  it  that  the  arteries  owe  the  faculty  of  remaining 
open  when  they  are  empty.  When  isolated,  it  possesses  a 
feeble  power  of  resistance  and  elasticity,  in  the  longitudinal 
direction  of  the  arteries,  but  is  very  tenacious  and  elastic  in 
the  direction  of  its  fibres,  i.  e.  in  that  of  the  circumference  of 
the  vessel.  The  firmness  and  elasticity  of  the  fibres,  which 
form  it,  successively  diminish  from  the  large  towards  the 
small  arteries.  It  has  been,  by  turns,  compared  and  likened 
to  the  muscular  fibre  in  general,  the  muscular  fibre  of  the 
uterus,  and  the  fibrous  or  ligamentous  tissue;  it  constitutes  a 
species  of  elastic  tissue,  a  peculiar  tissue,  but  participating  of 
the  characters  of  the  muscular  and  ligamentous  fibres. 

§412.  The  inner  membrane  of  the  arteries,  which  is  also 
named  the  nervous,  arachnoid,  common,  &c.  is  the  thinnest  of 
the  three.  It  is  continued  from  the  ventricles  of  the  heart 
into  the  arteries;  by  it  the  greater  part  of  the  semi-lunar  valves 
of  the  arteries  are  formed.  In  the  larger  branches,  when  empty, 
it  presents  some  longitudinal  folds,  and  small  transverse  ones 
in  the  arteries  of  the  ham  and  elbow-joint;  it  is  equally  wrin- 
37 


280  GENERAL  ANATOMY. 

kled  in  the  retracted  arteries  after  amputation.  Its  inner  sur- 
face is  smooth,  polished,  moist,  and  in  contact  with  the  blood; 
its  outer  surface  adheres  to  the  middle  membrane.  In  the 
arterial  trunk,  it  can  be  divided  into  several  layers.  The  in- 
nermost is  extremely  thin,  and  transparent;  the  others  are  of 
an  opaque  white,  and  passes  insensibly  into  the  middle  mem- 
brane; it  is  to  this  part  especially,  that  the  name  of  nervous 
membrane  has  been  given.  In  the  branches,  it  forms  only  a 
single  indivisible  lamina.  No  appearance  of  fibres  is  distin- 
guished in  this  membrane,  which  is  very  dense ;  it  tears  nearly 
with  the  same  facility  in  all  directions.  It  has  little  elasticity. 
It  has  been  compared  to  the  serous  membrane  and  the  mucous 
or  cellular  tissue.  It  is  not  vascular  like  the  serous  membrane 
generally;  and  it  is  to  the  arachnoid  membrane  that  it  bears 
the  greatest  resemblance. 

§  413.  Cellular  tissue,  vessels  and  nerves,  also  enter  into 
the  composition  of  the  arteries. 

The  cellular  tissue  which  penetrates  into  the  outer  mem- 
brane, and  which  unites  it  to  the  middle  one,  is  sufficiently 
apparent,  but  beyond  this,  it  is  so  rare  and  compact,  that  its 
existence  has  been  doubted.  However,  when  by  dissection 
the  outer  membrane,  and  the  greater  part  of  the  thickness  of 
the  middle  one  are  removed  from  an  artery,  there  spring  from 
the  uncovered  part  fleshy  granulations,  as  from  the  remainder 
of  the  wound. 

§  414.  The  arteries  and  veins  of  the  arteries  (vctsa  artcria- 
rum9)  are  furnished  by  the  neighbouring  vessels,  and  become 
very  apparent  in  the  outer  membrane  by  injections,  and  even 
sometimes  without  them,  particularly  in  young  subjects.  They 
have  been  traced  to  their  entrance  into  the  middle  membrane, 
but  no  farther. 

What  are  called  exhalent  and  absorbent  vessels,  or  more 
correctly  the  unknown  passages  of  exhalation  and  inhalation, 
are  demonstrated  iti  the  parietes  of  the  arteries  by  the  fact 
itself,  for  in  inflammation  of  the  arteries  an  exhalation  occurs 
at  their  internal  surface;  and,  in  cases  of  ligatures,  the  internal 
coagulum  is  absorbed. 


OF  THE  ARTERIES.  281 

§  415.  The  nerves*  of  the  arteries  are  derived  from  the  spi- 
nal marrow  and  the  ganglia.  The  arteries  of  the  organs  of  the 
vegetative  functions  receive  theirs  from  the  ganglia,  the  others 
from  the  spinal  marrow.  The  nerves  of  the  arteries  form 
around  them  a  net-work  analogous  to  those  which  the  pneu- 
mogastric  nerves  form  around  the  resaphagus,  and  thus  accom- 
pany them  into  the  interior  of  the  organs.  But,  moreover, 
some  filaments  terminate  in  the  outer  layer,  and  others  reach 
the  middle  membrane,  on  which  they  spread  out  into  a  very 
delicate  net-work.  The  former  are  soft  and  flat,  the  latter, 
which  are  filiform  and  of  extreme  minuteness,  have  more  con- 
sistence, and  pass  through  a  shorter  course.  All  the  arteries 
do  not  receive  an'  equal  number  of  nerves;  the  pulmonary  ar- 
teries receive  fewer  than  the  aorta  and  its  divisions.  The 
smaller  the  arteries  are,  the  more  abundant  are  the  nerves. 
The  arteries  of  the  brain  are  furnished  with  nerves  only  to 
the  place  where  they  penetrate  into  the  cerebral  substance. 
In  old  age,  the  nerves  of  the  arteries,  especially  those  of  the 
middle  membrane,  become  less  apparent.  The  great  number 
of  nerves  which  are  distributed  to  the  arteries,  shows  that  a 
close  connexion  exists  between  the  nervous  system  and  the 
circulatory  apparatus,  or  between  the  nerves  and  the  blood. 

§  416.  The  most  physical  properties  of  the  arteries  are  the 
toughness  of  their  tissue,  its  tenacity  and  elasticity.  It  is  to  .the 
firmness  of  the  middle  membrane  that  they  especially  owe  the 
power  of  preserving  a  considerable  part  of  their  tubular  form, 
even  when  empty  of  blood.  Their  specific  gravity  is  about 
108.  Their  thickness,  which  is  generally  considerable,  is  a 
little  augmented  when  they  are  empty.  It  is  also  somewhat 
greater  on  the  convex  side  of  the  curvatures  than  on  the  oppo- 
site side,  being  nearly  in  the  proportion  of  8  to  7.  It  increases 
proportionally  to  the  caliber  of  the  arteries  in  the  same  degree 
as  the  latter  diminishes;  it  is  not  the  same,  however,  in  all  the 
arteries  of  the  same  diameter;  thus  the  parietes  of  the  arte- 
ries of  the  brain  are  very  thin,  and  those  of  the  limbs  are 
thick. 

*  A.  Wrisberg,  loc.  cil. —  Lucre,  quadam  nlserv.  anaf.  circa  Ntrvos  arfm'aa 
adrnufcs  ef  comitantes.  -Ito  rum  Jfg.  Fruncof.  ad  Mnenum,  1810. 


GENERAL  ANATOMY. 

§417.  Clifton  Wintringham  has  examined  the  tenacity  of 
the  arteries  and  the  resistance  they  oppose  to  rupture.  I  have 
also  made  some  experiments  on  this  subject.  These  vessels 
have  a  great  power  of  resistance,  which  is,  generally,  in  pro- 
portion to  their  thickness.  That  of  the  aorta  is  superior  to 
that  of  the  pulmonary  artery.  In  the  same  degree  as  the  ar- 
teries diminish  in  size,  their  absolute  tenacity  diminishes,  but 
their  relative  thickness  and  softness  increase,  their  extensi- 
bility and  relative  resistance  augment.  The  resistance  is  not, 
however,  the  same  in  all  the  arteries  of  the  same  volume:  that 
of  the  iliac  artery  is  greater  than  that  of  the  carotid.  The  te- 
nacity in  the  longitudinal  direction  is  almost  entirely  owing 
to  the  outer  membrane.  The  circular  resistance,  which  is 
much  stronger,  is  owing  to  the  middle  and  outer  layers.  The 
inner  membrane  has  very  little  power  of  resistance  in  either 
direction. 

§418.  The  most  important  physical  property  of  the  arte- 
ries is  their  elasticity.  If  they  be  distended  in  the  longitudi- 
nal direction,  they  yield  and  elongate,  to  return  suddenly  to 
their  former  state  whenever  the  distention  ceases.  If  they  be 
distended  transversely,  the}''  are  less  distensible  and  spring 
back  with  greater  force.  If  by  injection  or  insufflation  they 
are  distended  to  excess,  they  enlarge  a  little,  elongate,  and 
when  the  effort  ceases,  they  spring  back  upon  themselves  and 
expel  part  of  their  contents.  If  they  be  bent,  they  return  to 
their  former  direction;  if  they  be  flattened  by  pressure,  they 
resume  their  cylindrical  form.  During  life,  they  are  in  a 
state  of  elastic  tension,  which,  when  they  are  divided,  causes 
the  ends  to  retract. 

The  largest  arteries  possess  a  very  distinct  elasticity,  but  it 
diminishes  successively  in  the  smaller  ones. 

§  419.  The  arteries  are  also  susceptible  of  a  slow  extensibi- 
lity and  retractibility.  When  a  principal  artery  is  obliterated, 
the  collateral  arteries,  in  replacing 'it  in  its  functions,  enlarge 
and  acquire,  in  a  short  time,  a  considerable  volume;  this  en- 
largement is  of  the  same  kind  as  ordinary  growth,  but  is  much 
more  rapid:  the  artery,  on  the  contrary,  which  ceases  to  af- 


OF   THE   ARTERIES.  285 

ford  a  passage  to  the  blood,  gradually  shrinks,  and  ultimately 
disappears  more  or  less  completely. 

§  420.  The  vital  properties  of  the  arteries,  like  those  of  the 
other  parts,  are  relative  both  to  their  own  nutrition  and  to 
their  action  in  the  organism.  The  force  of  formation  is  mani- 
fest in  them  by  their  accidental  productions,  and  less  in  the 
reparation  of  their  lessions.  Irritability  is  susceptible  to  a 
certain  degree;  sensibility  is  much  less  obvious. 

§421.  Arterial  irritability,*  called  also  tonicity,  contractili- 
ty, vital  force  of  the  arteries,  power  of  contraction,  or  the 
force  by  which  the  parietes  of  the  arteries,  during  life,  draw 
towards  its  axis  without  even  having  distended,  has  been  a 
subject  of  great  controversy  among  physiologists. 

Haller,  who  admits  that  the  middle  coat  of  arteries  is  of  a 
muscular  nature,  confesses  that  his  experiments  have  taught 
him  nothing  positive  on  their  contractility,  and  that  these 
vessels  have  not  always  given  evidence  of  the  effects  produced 
on  them  by  chemical  and  mechanical  stimulants.  Bichat, 
Nysten,  and  Magendie,  have  all  denied  the  irritability  of  the 
arteries.  Bichat  founds  his  opinion  on  the  circumstance,  that 
mechanical  irritation  within  or  without  the  vessel  does  not 
produce  motion;  if  an  artery  be  open  lengthwise,  its  edges 
do  not  curl;  if  it  be  separated  from  the  body,  it  evinces  no 
mark  of  contractility;  if  it  be  dissected  layer  by  layer,  its 
fibres  are  not  perceived  to  palpitate ;  if  the  finger  be  intro- 
duced into  an  artery  during  life,  it  is  not  firmly  grasped  by  it;  if 
an  artery  be  intercepted  between  two  ligatures,  it  experiences 
only  a  motion  communicated  to  it.  The  contraction  produced 
by  acids,  is  a  horny  induration,  and  the  action  of  alkalies  is 
next  to  nothing. 

The  greater  number  of  anatomists  and  physiologists,  how- 
ever, are  of  a  contrary  opinion,  founding  it  on  a  great  number 
of  facts.  Verschuir  and  Hastings  have  observed  mechanical 

*  See  Chr.  Kramp,  de  vi  vitali  arteriarum.  Argent,  1785. — C.  H.  Parry, 
An  exper.  inquiry  info  the,  puke  and  oilier  prop,  of  arteries,  &c.  Bath,  1816. 
—Oh.  H.  Parry,  Additional  experi.  on  the  arteries,  &c.  Lond.  1819. — Hast- 
ings, be.  cit. 


284  GENERAL  ANATOMY. 

irritation  to  produce  the  contraction  of  the  arteries.  Zi  miner- 
mann,  Parry,  Verschuir,  and  Hastings  have  remarked  that  mi- 
neral and  vegetable  acids  cause  the  same  effect.  Thomson  and 
Hastings  have  seen  the  same  thing  occur  by  the  action  of  am- 
monia. Verschuir,  Hunter,  and  Hastings  have  observed  the 
simple  action  of  the  air  and  of  temperature  to  produce  this  con- 
traction. Hastings  has  also  obtained  the  same  result  by  the 
application  of  oil  of  turpentine,  the  tincture  of  cantharides,  the 
solution  of  muriate  of  ammonia,  and  of  sulphate  of  copper. 
Bikker  and  Van  den  Bosch  have  caused  the  contraction  of  the 
arteries  by  electricity;  Guilo  and  Rossi  by  galvanism;  Home 
Jias  observed  it  even  on  the  application  of  an  alkali  on  the 
nerve  adjoining  an  artery.  Vital  contractility,  little  apprecia- 
ble in  the  larger  arteries,  augments  successively  in  the  smaller 
.ones. 

We  may  also  cite  as  a  farther  proof  of  the  existence  of  the 
irritability  .of  the  arteries,  the  augmentation  of  their  contrac- 
tion in  inflammation  and  in  neurosis.  Thus,  in  panaris,  in 
angina  tonsillaris,  in  tic  douloureux,  &c.;  we  see  and  feel  the 
arteries  beat  on  one  side  much  more  than  on  the  other.  We 
sometimes  observe  differences  of  the  same  kind  in  hemiplcgia. 
The  same  thing  also  occurs  in  pregnancy,  and  in  many  other 
hygid  or  morbid  phenomena,  accompanied  with  a  local  de- 
velopment of  vessels. 

We  may  therefore  conclude,  from  what  proceeds,  that  during 
life  the  arteries  possess  both  elasticity  and  irritability;  that 
elasticity  predominates  in  the  large,  and  irritability  in  the  small 
arteries;  that  arterial  irritability  is  more  or  less  dependent  upon 
the  nervous  influence.  In  the  course  of  time,  the  vasa  vaso- 
ntm  diminishing,  the  nerves  of  the  arteries  gradually  disap- 
pearing, and  the  middle  membrane  becoming  harder,  the  arte- 
rial irritability  lessens  more  and  more,  and  even  the  elasticity 
itself  is  greatly  impaired. 

§  422.  The  sensibility  of  the  arteries  is  null  or  extremely 
obscure.  Verschuir  relates  one  single  experiment  in  which 
an  animal  seemed  to  feel  pain  on  the  application  of  a  mineral 
acid.  According  to  Bichat,  on  injecting  an  irritating  liquid 
a  lively  pain  appears  also  to  be  produced. 


OF  THE  ARTERIES.  285 

§  423.  The  function  of  the  arteries  is  to  convey  the  Wood 
from  the  heart  to  all  the  parts  of  the  bod}-.  When  the  ventri- 
cles of  the  heart  propel,  while  contracting,  a  new  supply  of  li- 
quid into  the  arteries,  already  full  with  blood  in  motion,  the 
velocity  of  the  motion  is  increased  in  all  the  arteries:  the  ob- 
servation of  the  wound  of  an  artery  proves  it.  Another  effect 
of  the  systole  of  the  ventricles,  generally  admitted,  is  the  dila- 
tation of  the  arteries.  Experiments  have  been  cited  in  sup- 
port of  this  dilatation;  other  interesting  experiments  of  Doctor 
Parry  appear  to  contradict  it;  it  really  exists,  however,  but  it 
is  very  inconsiderable.  Another  effect,  but  more  appreciable, 
produced  by  each  systole,  is  the  elongation  of  the  arteries. 
The  action  exercised  by  the  arteries  in  order  to  send  forward 
the  blood,  is  their  elastic  return  on  themselves,  which  narrows 
and  shortens  them,  and  consequently  diminishes  their  capacity, 
and  moreover,  a  force  of  vital  contraction  which  is  added  to 
elasticity  in  the  middle  sized  arteries,  and  this  vital  contrac- 
tion exists  exclusively  in  the  small.  The  velocity  of  the  course 
of  the  arterial  blood  generally  diminishes  from  the  trunks  to 
the  last  ramifications;  this  velocity  presents  besides  local  va- 
rieties, either  permanent  or  accidental. 

The  function  of  the  arteries  is  therefore  to  convey,  like  ca- 
nals, the  blood  in  all  the  parts  of  the  body,  and  like  contrac- 
tile canals,  to  communicate  to  it  a  part  of  the  motion  with 
which  it  is  animated.  The  action  of  the  arteries  on  the  blood 
has  been  at  times  exaggerated  and  at  others  too  little  appre- 
ciated. It  is  very  certain,  1st,  that  the  vessels  appear  before 
the  heart,  both  in  the  animal  series  and  embryo;  2d,  that  the 
monstrous  foetus  without  a  head  is  deprived  of  a  heart;  3d,  that 
in  fishes  there  is  no  aortic  ventricle,  and  that  even  in  man  the 
vena  portarum  (sect,  iii.)  is  equally  deprived  of  a  muscular 
agent  calculated  to  communicate  an  impulsion;  4th,  that  in  the 
reptiles  from  which  the  heart  has  been  removed,  the  motion 
of  the  blood  continues  for  a  long  time.  All  these  facts  evi- 
dently prove  that  the  vessels  are  an  agent,  and  are  even  the 
primitive  agent  of  the  motion  of  the  blood.  The  arteries  par- 
ticipate in  this  movement  by  their  elasticity  and  irritability. 

But  it  is  no  less  certain,  that  in  animals  provided  with  a 


286  GENERAL  ANATOMY. 

heart,  this  organ  becomes  a  powerful  agent  of  the  movement 
of  the  blood;  it  is  thus,  that  by  its  own  action  the  arterial  cir- 
culation, although  continuous,  is  pulsatory;  it  is  thus  that  the 
circulation  takes  place  in  the  sturgeon,  although  the  aorta  is 
inclosed  in  a  bony  canal;  in  the  same  manner  in  man,  the  aorta 
and  its  principal  branches  may  be  ossified  without  materially 
impairing  the  regularity  of  the  course  of  the  blood.  We  must 
hence  conclude  that  both  these  powers  (that  of  the  heart  and 
that  of  the  arteries,)  contribute  to  the  performance  of  the  cir- 
culation, and  that  one  may  in  a  measure  supply  the  action  of 
the  other.  But  the  action  of  the  heart  on  the  blood  gradually 
diminishes,  and  that  of  the  vessels  augments,  in  proportion  as 
it  is  more  distant  from  the  centre  of  circulation.  The  vital 
contraction  of  the  arteries  is  also  one  of  the  causes  of  their 
emptiness  in  the  dead  body.* 

§  424.  The  arterial  circulation  is  accompanied  with  a  move- 
ment called  pulse.  At  different  times  it  was  ascribed  to  the 
alternate  dilatation  and  contraction  of  the  arteries;  to  the  elon- 
gation of  these  vessels,  and  to  the  motion  which  results  from 
it;  to  the  pressure  of  the  finger  while  feeling  it,  or  to  several 
of  these  causes  combined.  The  number  of  pulsations  de- 
pend solely  upon  that  of  the  contraction  of  the  heart.  The 
volume  or  fullness  of  the  pulse  is  owing  to  the  quantity  of  the 
blood  contained  in  the  arteries;  its  duration,  to  that  of  the  con- 
tractions of  the  heart;  its  strength,  to  the  quantity  of  the  blood 
propelled  by  the  heart,  to  the  power  with  which  it  is  pushed, 
to  the  quantity  contained  in  the  arteries,  and  to  that  which 
passes  through  the  capillary  vessels. 

The  feeling  of  the  pulse  has  for  its  object  the  examination 
of  the  state  of  the  circulation,  and  of  the  powers  which  move 
the  blood,  viz.,  the  heart  and  vessels. 

*  With  all  due  deference  for  the  opinion  of  our  author,  we  beg  to  differ 
with  him  on  this  point.  We  believe  that  the  new  experiments  on  endos- 
mose  and  exosmose  tend  to  prove  the  contrary  position.  We  conceive  that 
the  larger  arteries  have  lost  at  this  time  all  power  of  vital  contract  here 
ascribed  to  them,  when  the  blood  is,  by  an  action  in  the  capillaries,  as  y«  t 
not  positively  demonstrated,  drawn  from  the  larger  arteries  through  the  ca- 
pillaries into  the  veins. 


OF  THE  ARTERIES.  287 

The  parietes  of  the  arteries  augment  in  thickness  and  densi- 
ty during  the  period  of  growth;  they  still  continue  to  increase 
in  density  during  the  remainder  of  life. 

The  variations  in  the  distribution  of  the  arteries  arc  much 
more  frequent  than  is  generally  imagined.  Bichat  and  Meek- 
el*  have  justly  remarked,  that  they  are  at  least  as  often  met 
with,  as  those  of  the  veins,  and  perhaps  even  more  frequently. 
It  is  especially  in  the  larger  arteries  that  they  are  remarkable,! 
both  by  their  frequency,  and  by  a  sort  of  regularity  or  sym- 
metry, and  by  the  resemblance  they  then  present  with  the 
regular  state  of  certain  animals. 

§  425.  Besides  the  accidental  vessels  already  indicated  [371,] 
when  a  principal  artery  is  interrupted  in  its  continuity,  there 
are  established  also  other  passages  for  the  circulation.  These 
new  passages  are  commonly  formed  out  of  the  ancient  small 
vessels,  but  greatly  enlarged,  which  were  previously  white, 
by  their  extreme  thinness,  become  red,  or  which,  being  red 
and  capillary,  become  more  voluminous;  but  which,  before 
this  circumstance,  formed,  by  their  anastomoses,  collateral 
passages  [350].  In  certain  cases  circulation  is  re-established 
through  passages  entirely  of  a  new  formation.  This  fact, 
the  existence  of  which  was  suspected  by  J.  Hunter,  by  Mau- 
noir  and  even  by  Jones,  although  he  controverted  Maunoir's 
opinion,  has  been  put  beyond  question  by  the  experiments 
of  Dr.  Parry.J  If  the  carotid  artery  of  a  sheep  be  tied,  or 
a  part  be  removed,  an  artery  which  furnishes  no  branches  in 
the  whole  extent  of  the  neck,  we  find  some  time  after,  the  cir- 
culation re-established  in  the  very  place  where  the  artery  has 
been  obliterated  or  cut  off,  by  several  branches  nearly  parallel, 
occupying  the  interval  which  exists  between  the  divided  ex- 
tremities of  the  artery. 

§426.  The  general  inflammation  of  the  arteries  is  of  a  rare 
occurrence;  their  local  inflammation  is, on  the  contrary, often 
met  with.  Simple  redness,  however,  is  not  sufficient  to  charac- 
terize it;  there  is,  moreover,  some  thickening  or  softening  in 

*  Deutschus  archiv.  fur  die  physiologic. 

f  Fr.  Ticdemann,  Tabula  artcriarum  corp.  humani.     Calsruhae,  1822. 

*  Loc.  cit. 

38 


288  GENERAL  ANATOMY. 

the  parietes,  and  internally  a  plastic  exudation,  sometimes  pus, 
and  at  others  more  or  less  extensive  ulcerations. 

§  427.  The  wounds*  of  the  arteries  present  anatomical  con- 
siderations of  great  importance.  The  puncture  of  an  artery 
gives  rise  to  a  feeble  hemorrhage  if  the  vessel  be  surrounded 
by  cellular  tissue;  but  it  is  greater  if  it  be  deprived  of  its 
sheath.  The  hemorrhage  is  arrested  by  the  coagulation  of  the 
blood,  which  is  afterwards  gradually  absorbed;  there  is,  during 
a  short  time,  a  small  enlargement  opposite  the  puncture;  after- 
wards so  very  perfect  a  cicatrix  is  formed,  that  it  is  impossi- 
ble to  perceive  it.  A  small  incision,  lengthwise  with  the 
vessel,  opens  a  little,  and  gives  rise  to  a  hemorrhage  greater 
than  that  produced  by  the  puncture.  The  cure  is  sometimes 
effectuated  afterwards,  and  in  the  same  manner.  A  transverse 
incision  produces,  by  the  considerable  separation  of  its  edges, 
a  more  or  less  serious  hemorrhage,  according  to  the  extent 
of  the  laceration  of  its  cellular  sheath.  The  hemorrhage  is 
the  more  serious,  the  more  the  incision  involves,  more  than 
one  half  of  the  circumference  of  the  vessel,  a  case  in  which,  if 
left  to  itself,  it  continues  or  is  renewed  after  being  stopped, 
until  death  takes  place.  In  the  cases  in  which  the  lesion  reaches 
only  a  small  part  of  the  circumference,  if  the  sheath  exists, 
after  having  bled  more  or  less,  the  blood  infiltrates  and  coagu- 
lates in  it,  and  sometimes  a  cicatrix  is  formed,  which,  in  man, 
is  much  less  solid  than  the  original  parietes  of  the  artery,  and 
which  becomes  commonly  the  seat  or  the  cause  of  a  consecu- 
tive aneurism.  When,  on  the  contrary,  the  transversal  divi- 
sion is  much  greater  than  one  half  of  the  circumference,  the 
retraction,  as  well  as  the  diminution  of  its  size,  which  result 
from  it,  is  such,  that  if  the  sheath  still  exists,  the  blood  infil- 
trates, stops,  and  coagulates  in  it,  and  the  cure  may  also  take 
place.  But  in  order  that  this  may  occur,  the  complete  divi- 
sion of  the  artery  is  accomplished,  and  then  this  case  belongs 
to  the  following. 

§428.  Whenever  an  artery  of  a  mean  caliber  is  cut  across, 

*  J.  F.  D.  Jones,  on  the  process  employed  by  nature  in  suppressing  hem- 
orrhage, 6fc.  Lond.  1810.— Beclard,  loc.  cit. 


OP  THE  ARTERIES.  289 

either  on  a  surface,  the  result  of  an  amputation,  or  in  the  con- 
tinuation of  the  soft  parts,  the  blood  issues  in  a  full  stream  and 
by  a  constant  jet,  alternately  rising  and  lowering  until  the 
circulation  is  greatly  enfeebled;  then  the  bleeding  diminishes 
and  stops,  either  to  recommence  one  or  more  times  when  the 
weakness  has  ceased,  and  to  continue  even  to  death,  or  ceases 
altogether.  In  this  latter  case,  very  rare  in  the  human  species, 
the  artery  being  retracted  in  its  sheath  and  in  the  surround- 
ing cellular  tissue,  the  blood  infiltrates  and  coagulates  around 
the  end  of  the  vessel;  it  coagulates  also  in  the  end  itself  to  a 
greater  or  smaller  distance,  always  determined,  however,  by 
the  situation  of  the  nearest  branch,  through  which  the  circu- 
lation still  continues  to  take  place.  The  extremity  of  the  arte- 
ry is  then  obstructed  and  plugged,  nearly  in  the  same  manner 
as  is  the  mouth  of  a  bottle  by  the  cork,  and  by  the  wax  with 
which  it  is  covered.  The  artery  being  no  longer  influenced  by 
the  alternate  distention  it  previously  experienced,  gradually 
shrinks;  its  divided  extremity  undergoes  traumatic  inflamma- 
tion, and  becomes  the  seat  of  a  plastic  exudation;  the  blood, 
cogulated  internally  and  externally,  is  gradually  absorbed,  the 
artery  cotinues  to  contract,  it  is  converted  into  a  mere  cord, 
and  commonly  disappears,  or  is  changed  into  cellular  tissue  as 
far  as  the  neighbourhood  of  the  nearest  branch,  which  con- 
tinues to  carry  on  the  circulation. 

§  429.  When  an  artery  is  distended  lengthwise,  it  greatly 
elongates  at  first  by  sliding  in  its  sheath,  favoured  by  the  cellu- 
lar tissue  which  surround  it;  after  yielding  a  great  deal  with- 
out breaking,  it  begins  to  tear  internally.  The  external  mem- 
brane is  the  last  part  torn,  after  being  elongated  and  thinned 
nearly  in  the  manner  of  a  tube  of  glass  melted  and  drawn  over 
a  lamp.  After  being  torn,  the  extremities  of  the  artery  re- 
treat less  than  they  have  yielded,  and  the  blood  jets  out,  at 
first,  as  in  the  preceding  case;  but  ordinarily,  it  soon  stops, 
never  to  reappear.  This  quick  and  entire  cessation  of  the 
hemorrhage,  which  almost  always  occurs  in  similar  cases,  has 
been  ascribed  to  the  retraction  of  the  artery  and  to  other  ima- 
ginary causes.  I  am  convinced,  by  many  experiments  per- 
formed on  animals,  and  by  many  observations  made  on  man, 


290  GENERAL  ANATOMY. 

that  we  ought  to  attribute  this  remarkable  phenomenon,  to  the 
more  or  less  multiplied  internal  ruptures  that  the  artery  ex- 
periences before  its  total  division  at  any  one  point.  The  phe- 
nomena which  follow  are  the  same  as  after  the  transversal 
section.  (428.) 

§  430.  A  ligature  applied  to  an  artery,  either  when  entire, 
or  when  it  is  cut  as  at  the  surface  of  an  amputated  limb,  suffi- 
ciently tight  to  arrest  the  circulation  in  the  vessel,  cuts  the  in- 
ner and  middle  membrane,and,if  the  artery  is  healthy,  without, 
divides  the  outer  one.  If  the  ligature  is  permitted  to  remain, 
the  blood  stopped  in  the  vessel  coagulates  in  its  cavity  as  far 
as  to  the  nearest  branch.  The  division  experienced  by  the  in- 
ner membranes, the  pressure  exercised  on  the  external  ones  and 
the  presence  of  the  ligature,  induce  an  effusion  of  organizable 
matter,  which  produces  at  first  the  agglutination  of  all  the  in- 
jured parts;  the  part  embraced  within  the  ligature  is  at  first 
softened,  is  afterwards  divided  by  the  effect  of  inflammation, 
and  the  ligature  comes  off.  The  changes  which  follow  in  the 
vessel  are  the  same  as  after  the  transverse  section.  (428.) 

§  431.  In  the  three  kinds  of  wounds  of  which  we  have  just 
treated,  (428,  430.)  the  ulterior  phenomena  are  different,  ac- 
cording as  they  are  made  on  an  amputated  surface  or  in  the 
continuity  of  the  parts.  In  an  amputated  surface,  the  princi- 
pal artery  is  not  only  obliterated,  but  also  its  branches  termi- 
nating at  the  surface,  so  that  the  trunk  itself  is  more  or  less 
narrowed.  In  the  other  case,  on  the  contrary,  the  branches 
which  arise  from  the  artery  on  which  a  ligature  has  been  ap- 
plied, divided  or  torn,  not  only  continue  to  carry  on  the  cir- 
culation, but  dilate  in  order  to  supply  the  principal  trunk; 
they  thus  keep  up,  even  to  the  point  where  they  arise,  the 
fluidity  of  the  blood,  its  motion,  and  its  influence  on  the  vessel. 
It  is  to  this  difference  that  must  be  ascribed  the  frequency  of 
the  primitive  reunion  of  divided  arteries  on  an  amputated  sur- 
face, and  the  comparative  few  cases  of  this  happy  result,  when 
the  division  of  the  artery  happens  in  the  soft  parts. 

§432.  We  sometimes  find  a  cartilaginous  production  or 
transformation,  with  thickening  of  the  parietes  of  the  arteries, 
commonly  in  a  somewhat  confined  extent.  Athcromatous, 


OP  THE  ARTERIES.  291 

steatomatous  productions,  &c.  are,  like  the  preceding,  only  the 
beginning  of  the  calcarious  ossification  of  which  the  arteries 
are  so  often  the  seat.  This  ossification  is  of  two  kinds,  acci- 
dental and  senile.  The  first  has  its  seat  between  the  inner  and 
middle  membranes,  and  is  preceded  by  one  of  the  above  men- 
tioned alterations.  The  second,  on  the  contrary,  has  its  seat 
in  the  middle  membrane,  and  consists  in  a  transformation  of 
its  fibrous  rings  into  osseous  ones,  more  or  less  extensive.  The 
different  parts  of  the  arterial  system  are  not  every  way  equally 
predisposed  to  it.  The  aortic  system  is  oftener  affected  by  it 
than  the  pulmonary.  The  internal  projections  of  the  arteries, 
and  the  valves  of  their  trunks,  are  frequently  the  seat  of  this 
affection;  the  aorta  and  its  principal  branches  are  often  in  the 
same  case;  oftener  in  the  arteries  of  the  inferior  members  than 
in  those  of  the  superior  extremities;  pretty  often  in  those  of 
the  muscles,  heart,  brain  and  spleen  ;  but  rarely  in  those  of  the 
stomach  and  liver.  Finally,  Harvey,  Riolan,  and  Loder,  have 
observed  the  whole  arterial  system  ossified.  The  ossification 
of  the  arteries  most  generally  occurs  in  old  age;  accidental  os- 
sification, however,  is  also  sometimes  observed  in  young  sub- 
jects, and  in  early  infancy.  This  affection  of  the  arteries  is 
not  so  frequent  in  woman  as  in  man.  It  is  much  more  com- 
mon in  cold  than  in  warm  climates. 

The  effect  of  arterial  ossification,  and  especially  of  that  which 
is  accidental,  is  to  produce  the  wearing  of  the  membranes  be- 
tween which  it  is  placed.  The  ossification  of  the  arteries  has 
been  ascribed  to  a  great  many  causes.  The  accidental  one  is 
a  true  production  or  deposition;  that  which  is  senile  seems  to 
be  the.  last  conditions  of  the  successive  changes  that  the  middle 
membrane  experiences  during  life,  but  in  the  first  period  of 
which  is  soft  and  red. 

§  433.  Excrescences  of  a  fleshy  consistence  are  sometimes 
found  attached  to  the  internal  surface  of  arteries,  and  espe- 
cially to  the  semi-lunar  valves  which  are  at  their  entrance. 

§  434.  The  dilatation  of  the  arteries  is  a  very  common  affec- 
tion; it  may  consist:  1st,  in  a  simple  loss  of  elasticity  without 
any  apparent  alteration  of  the  parietes;  2d,  in  an  alteration  of 
the  dilated  parietes. 


292  GENERAL  ANATOMY. 

Simple  dilatation  is  especially  met  with  in  the  large  trunks; 
it  affects  equally  the  whole  circumference,  and  the  tumour 
resulting  from  it  has  an  ovoid  form.  It  has  often  been  ob- 
served in  the  aorta,  particularly  at  its  curvature,  and  some- 
times in  the  pulmonary  artery. 

The  dilatation,  with  an  alteration  of  the  parietes,  affects  the 
aorta  and  the  different  parts  of  the  aortic  system  even  to  the 
ramifications.  The  arteries  of  the  superior  members  are  more 
seldom  affected  than  those  of  the  inferior.  The  alteration  and 
dilatation  which  results  from  it,  are  most  commonly  lateral. 
This  is  the  affection  that  authors  have  described,  since  Fernel, 
under  the  name  of  true  aneurism.  The  altered  parietes  are 
rather  thickened  than  thinned  in  it.  The  blood  contained  in 
these  two  kinds  of  dilatations  is  fluid. 

§  435.  Aneurism  is  caused  by  the  injury  or  rupture,  in  a 
word,  by  the  solution  of  continuity  of  the  arterial  parietes, 
commonly  preceded  by  the  dilatation  of  these  parietes,  and 
always  preceded  by  their  alteration.  It  consists  in  a  cavity 
formed  by  the  outer  membrane,  dilated  and  strengthened  on 
all  sides  by  the  cellular  tissue  and  by  the  other  surrounding 
parts ;  lined  internally  by  a  thin  and  in  some  places  polished 
membrane,  resembling  very  much  the  inner  membrane  of 
arteries.  This  cavity  communicates  with  that  of  the  vessel, 
through  a  passage  sometimes  regular,  at  others  irregular,  made 
in  the  inner  and  middle  membranes;  it  is  filled  with  coagu- 
lated blood,  and  with  layers  of  fibrine  more  or  less  firm,  dif- 
ferently altered,  and  perhaps  mixed  with  organizable  matter 
produced  by  the  parietes  of  the  cavity.  The  blood,  in  its  cir- 
culatory course,  penetrates  continually  into  the  accidental 
cavity. 

Sometimes  aneurisms  enlarge  indefinitely,  and  cause  death 
by  the  compression  they  produce  on  the  neighbouring  organs 
and  by  the  disturbance  of  their  functions.  At  others  it  is 
ruptured  either  externally  or  internally,  and  causes  death  by 
hemorrhage  or  by  effusion.  At  other  times  it  inflames,  sup- 
purates and  opens  like  a  large  abscess,  and  then  sometimes 
hemorrhage  occurs,  or,  on  the  contrary,  the  artery  being  ob- 
literated by  inflammation,  a  radical  cure  may  follow.  Some- 


OP  THE  VEINS.  293 

times  inflammation  terminates  in  the  gangrene  of  the  tumour, 
and  either  of  the  effects  here  above  mentioned  may  be  the 
result  of  the  separation  of  the  eschar.  Finally,  at  other  times, 
the  circulation  imperceptibly  diminishes  in  the  artery  affected 
with  aneurism,  and  becomes  at  the  same  time  more  and  more 
active  in  the  collateral  passages  or  vessels,  from  which  finally 
result  the  obliteration  of  the  affected  artery  as  far  as  the  neigh- 
bouring branches  of  the  tumour,  and  the  gradual  absorption 
of  the  latter. 

§436.  Arteries,  inflamed  or  affected  with  an  accidental 
production  in  their  parietes,  or  without  any  apparent  cause, 
instead  of  dilating  and  tearing,  are  sometimes  narrowed,  and 
even  are  obliterated  spontaneously.  Thus  the  aorta  has  been 
observed  narrowed  and  even  altogether  obliterated;  the  total 
obliteration  of  the  right  pulmonary  artery  has  also  been  re- 
marked. I  have  seen  once  that  of  the  carotid  artery,  several 
times  the  narrowing  of  the  caliber  of  the  brachial  trunk,  and 
often  the  narrowing  and  obliteration  of  the  crural  trunk  and 
of  its  branches.  This  is  the  ordinary  cause  of  senile  gangrene 
of  the  toes,  feet  and  legs;  this  change  occurring  in  a  part  and 
at  a  time  in  which  the  arterial  branches,  they  themselves 
being  affected  with  hardening,  are  no  longer  susceptible  of 
rapid  growth,  necessary  to  the  re-establishment  of  the  colla- 
teral circulation. 


SECTION  III. 

OP  THE  VEINS. 

§  437.  The  veins*  are  the  vessels  which  bring  back  to  the 
heart  the  blood  from  every  part  of  the  body. 

§  438.  We  have  already  seen  that  the  ancients  have  at  first 
made  no  distinction  between  the  veins  and  arteries.  Galen, 

*  Diatribe  anatomico-physiobgica  de  strudura  atque  vita  venarum,  Au- 
tore  H.  Marx,  in  8vo.  Carlsruhze,  1819. 


294  GENERAL  ANATOMY. 

who  distinguished  them  very  well,  placed  the  origin  of  the 
former  in  the  liver.  The  difference  and  connexion  between 
the  arteries  and  veins  have  been  perfectly  established  by  the 
discovery  of  the  circulation  of  the  blood  ;  since  that  time,  the 
study  of  the  venous  system  has  been  somewhat  neglected.* 

§  439.  The  veins,  like  all  the  vascular  system,  have  an  ar- 
borescent disposition ;  but  considered  with  respect  to  the  di- 
rection of  the  course  of  the  blood,  they  rather  resemble  the 
roots  of  a  tree,  than  its  branches.  Thus  their  origin  takes 
place  by  radicles,  which  correspond  to  the  ramuscules  of  the 
arteries;  their  termination  by  trunks  which  open  into  the 
heart,  like  the  origin  of  the  arteries;  their  course  presents  re- 
unions and  successive  divisions,  like  that  of  the  arteries.  If 
examined  then,  by  following  the  course  of  the  blood,  they 
present  a  contrary  disposition  to  that  of  the  arteries;  and  if 
considered  in  the  same  direction  as  the  arteries,  we  should 
follow  a  course  opposite  to  that  of  the  blood. 

§  440.  The  venous  system,  like  the  arterial,  is  double;  the 
one  general,  returns  the  blood  of  the  body  to  the  anterior  or 
right  auricle;  the  other  brings  back  the  blood  from  the  lungs 
to  the  other  auricle  of  the  heart.  There  is  moreover  a  parti- 
cular and  complicated  venous  system  in  the  abdomen:  this  is 
the  vena  porta,  the  disposition  of  which  must  be  the  object  of 
a  separate  investigation. 

§  441.  This  particular  venous  system  constitutes  of  itself  a 
whole  vascular  system,  that  is  to  say,  a  tree  having  a  trunk, 
roots  and  branches,  placed  between  the  last  ramuscules  of  the 
gastric,  intestinal  and  splenic  arteries,  which  are  continuous 
with  its  roots,  and  the  first  radicles  of  the  sub-hepatic  veins, 
which  are  the  continuation  of  its  branches.  This  vascular 
system,  if  we  take  into  consideration  its  disposition,  which  is 
ramified  in  opposite  directions,  resembles  the  veins  in  its  in- 
testinal half,  and  the  arteries  in  its  hepatic  half;  under  another 
relation,  it  is  indifferent  to  both,  being  intermediate,  for  it  is 
at  the  point  where  it  is  the  continuation  of  the  arteries,  that  it 
has  the  venous  disposition  and  vice  versa.  This  vascular 

*  Since  our  author  wrote  this  passage,  M.  Breschet  is  publishing  a  most 
splendid  work  on  the  venous  system;  which  see.  TRANS. 


OP  THE  VEINS.  295 

system  is  comprehended  in  the  general  venous  system,  espe- 
cially on  account  of  the  nature  of  the  blood  it  contains. 

§  442.  In  the  vertebrated  oviparous  animals  another  venous 
system,  analogous  to  the  intestino-hepatic  vessels,  is  found. 
This  particular  system*  is  formed  by  the  union  of  the  veins 
of  the  middle  region  of  the  body  only,  or  of  this  region  and 
of  the  tail,  which  veins  terminate  in  the  kidneys  in  the  same 
manner  as  the  arteries,  sending  sometimes  a  branch  to  the 
vena  porta,  that  is  lo  say,  to  the  liver.  I  have  sometimes  ob- 
served, in  the  dog,  the  vena  porta  to  have  one  or  two  renal 
terminations. 

§  443.  The  number  of  veins  is  in  general  greater  than  that 
of  the  arteries.  There  are  two  venae  cavae,  and  one  cardiac 
vein  to  correspond  with  the  single  trunk  of  the  aorta.  There 
are,  in  the  same  manner,  four  pulmonary  veins  to  correspond 
with  the  single  pulmonary  artery  and  its  two  branches.  But 
each  of  these  venous  divisions  corresponds  with  a  branch  of  a 
corresponding  artery.  In  almost  the  whole  extent  of  the  body, 
there  are  many  more  subcutaneous  veins  than  arteries,  and  in 
•deep  seated  parts,  there  are  almost  every  where  two  venae 
committes  for  a  single  artery.  In  the  stomach,  the  spleen,  the 
kidneys,  the  testicles,  the  ovaries,  and  some  other  parts,  the 
number  of  veins  is  equal  to  that  of  the  arteries.  In  some 
parts,  the  number  of  veins  is  even  less  than  that  of  the  arte- 
ries, as  for  instance,  in  the  umbilical  cord,  in  the  penis,  in  the 
clitoris,  in  the  gall-bladder,  surrenal  capsules,  &c.  But  this 
is  compensated  by  the  difference  of  capacity.  The  size  of  the 
veins  generally,  is  in  fact  more  considerable  than  that  of  cor- 
responding arteries. 

The  sum  of  the  veins,  or  their  total  capacity,  is  then  greater 
than  that  of  the  arteries.  Many  calculations  have  been  made 
respecting  it;  but  we  can  only  say  with  Haller,  that  the  veins 
are  at  the  least  double  of  the  arteries  in  capacity.  But,  indepen- 
dently of  individual,  accidental,  or  temporary  differences,  and 
those  which  depend  upon  the  kind  of  death,  it  continually 

*  Lud.  Jacobson,  de  systematc  venoso  peculiuri  in  pcrmultis  animalibus 
vbservato.     Hafnije,  1821. 
39 


296  GENERAL  ANATOMY. 

varies  with  age.  This  difference,  moreover",  is  not  the  same 
in  all  parts  of  the  body.  In  the  pulmonary  system  it  does 
not  exist,  for  the  veins  are  there  apparently  equal  in  capacity 
to  the  arteries.  This  is  also  the  case  with  the  renal  vessels. 
In  the  testicles,  on  the  contrary,  the  veins  are  greatly  superior 
to  the  arteries. 

§  444.  The  situation  of  the  veins  is  generally  the  same  as 
that  of  the  arteries,  these  two  kinds  of  vessels  accompanying 
each  other  in  their  course,  and  uniting  at  their  termination. 
Almost  every  where,  a  trunk,  a  branch,  or  a  twig  of  an  artery, 
is  accompanied  by  one  or  two  veins.  There  are,  however, 
exceptions:  thus,  in  the  cranium, the  spine,  the  eye  and  liver, 
the  arteries  and  veins  affect  different  situations  and  disposi- 
tions; the  vena  azygos,  the  trunk  of  the  intercostal  veins  in 
the  space  between  the  pericardium  and  liver,  is  not  accompa- 
nied by  an  artery,  and  this  is  also  the  case  with  the  subcutane- 
ous veins. 

§445.  The  veins  commence  by  capillary  or  microscopic 
radicles,  forming  a  continuation  of  the  ramuscules  of  the  arte- 
ries. These  radicles  are  colourless  or  red,  according  as  their 
diameter  admits  a  single  series  of  globules,  or  several  at  once. 
In  some  places,  as  in  the  intestine,  the  lungs,  &c.,  the  succes- 
sive reunion  of  the  radicles  of  the  veins  corresponding  with, 
and  entirely  similar  to  the  divisions  of  the  arterial  ramuscules. 
In  other  places  the  disposition  is  different.  Without  speaking 
of  the  erectile  or  cavernous  tissue,  in  which  the  swelling  and 
communication  of  the  veins  are  extreme,  in  many  other  parts 
they  have  different  dispositions  from  those  of  the  arteries: 
they  form  plexuses  at  the  neck  of  the  bladder,  in  the  spine, 
and  around  the  spermatic  artery,  wide  canals  in  the  spongy 
bones,  and  under  the  skin,  they  form,  by  their  numerous  com- 
munications, a  great  vascular  net-work  with  angular,  and  most 
ordinarily  meshes. 

They  are  not  so  regularly  cylindrical  as  the  arteries,  and  so 
far  from  following  a  regular  order  of  increase  in  the  volume 
of  the  trunks  and  of  decrease  in  their  total  capacity,  very 
large  branches  are  sometimes  seen  connected  with  a  trunk  of 
no  great  size,  which  depends  especially  on  the  softness  of  the 


OF  THE  VEINS.  297 

parietes  and  the  great  number  of  anastomoses.  The  commu- 
nication of  the  veins  present  all  the  varieties  already  indi- 
cated [356,]  and  moreover,  the  union  of  the  very  large  trunks, 
as  that  of  the  venae  cavae  by  the  vena  azygos;  the  union  of  su- 
perficial and  deep  seated  veins,  as  that  of  the  cranial  and  spinal 
veins  with  the  epicranial,  temporal,  cervical,  &e.,  that  of  the 
internal  and  external  jugular  veins,  and  that  of  deep  seated 
veins,  with  the  subcutaneous  veins  of  the  limbs. 

Generally,  the  veins  have  a  less  flexuous,  straighter,  and 
therefore,  shorter  course  than  the  arteries. 

The  variations  of  the  veins  have  been  a  little  exaggerated, 
and  those  of  the  arteries  have  been  somewhat  concealed.  The 
large  venous  trunks  especially  are  less  variable  than  they 
have  been  announced;  but  the  branches  and  twigs  are  very 
much  so. 

§  446.  The  interior  of  the  veins  present  a  great  number  of 
valves*  or  folds  of  the  inner  membrane,  which  constitute  a 
great  difference  between  them  and  the  arteries.  The  valves 
are  very  well  seen  by  examining  under  water  a  vein  split  open 
lengthwise. 

Each  valve  consists  in  a  fold  of  the  inner  membrane.  This 
fold  has  a  convex  edge,  adhering  to  the  parietes  of  the  vein 
on  the  side  towards  its  radicles,  and  a  concave  and  free  mar- 
gin, turned  towards  the  heart.  These  two  edges  are  some- 
what thicker  than  the  rest  of  the  fold;  one  of  the  surfaces 
is  turned  towards  the  cavity  of  the  vessel,  and  corresponds 
to  the  circulating  blood,  the  other  corresponds  to  the  parietes 
of  the  vein,  somewhat  dilated  at  this  point.  When  the  valve 
shuts,  the  surface,  which  corresponds  to  the  radicles,  becomes 
convex,  the  other  becomes  concave,  and  the  vein  slightly  en- 
larges; the  valves  are  so  much  the  more  broad  as  the  vein  is 
the  more  voluminous,  and  so  much  the  more  elongated  as  it 
is  smaller.  It  is  to  this  difference  especially  that  the  varieties 
of  form  described  by  Perrault  and  several  others  is  to  be  re- 
ferred. 

*  H.  Fabricio,  de  venarum  ostiolis,  in  op.  omn.—J.  G.  Schmiedt  and  Mei- 
bomius,  de  valvulls  seu  membranulis  vasorum  earumque  struct,  et  usu,  Helmst 
1682. — Perrault  Essais  de  physique,  torn.  iii. 


GENERAL  ANATOMY. 

Besides  the  inner  membrane,  there  exists  also  in  the  sub- 
stance of  the  valves,  dense  cellular  tissue,  and  sometimes  dis- 
tinct fibres;  sometimes  they  are  areolar  and  perforated  like 
lace.  In  the  veins  or  sinuses  of  the  dura  mater,  there  occur 
only  some  transverse  fibres,  which  may  be  considered  as  ru- 
dimentary valves. 

The  valves  are  generally  disposed  in  pairs  placed  alternative- 
ly, according  to  two  opposite  diameters  of  the  vein. 

They  are  three,  and  three  in  the  great  veins,  as  in  the  crural 
and  iliac;  they  are  seldom  observed  quadruple,  and  very  sel- 
dom or  never  quintuple.  In  twigs,  with  a  diameter  of  half  a 
line  and  less,  they  are  single. 

There  are  by  no  means  valves  at  all  the  places  where  a  twig 
unites  to  a  branch,  or  where  a  branch  opens  into  a  trunk;  nor 
are  they  everywhere  at  the  same  distance;  they  are  nowhere 
closer  to  each  other  than  in  the  smallest  veins.  Valves  are 
found  in  the  veins  of  the  extremities,  more  in  the  subcutane- 
ous than  in  the  deep  seated  ones,  in  those  of  the  face,  neck, 
tongue  and  tonsils,  at  the  termination  of  the  cardiac  vein,  in 
the  tegumentary  veins  of  the  abdomen,  in  those  of  the  testi- 
cles, penis  and  clitoris,  in  the  internal  and  external  iliac  veins, 
sometimes  in  the  renal  veins,  and  rarely  in  the  vena  azygos. 

There  are  none  in  the  encephalic,  spinal  and  diploic  veins, 
in  those  of  the  lungs,  in  the  vena  porta,  in  the  umbilical  vein, 
in  the  vense  cavaB,  if  we  except  those  at  the  entrance  of  the 
vena  azygos,  in  the  uterine  veins,  and  in  the  median  vein. 

There  are  generally  a  great  many  valves  in  the  superficial 
veins,  fewer  in  the  deep  seated  or  intermuscular  veins,  and 
still  fewer  in  the  veins  of  the  splanchnic  cavities;  they  are 
numerous  in  the  most  depending  parts,  and  therefore  in  the 
lower  extremities,  less  so  in  the  upper,  and  still  less  numer- 
ous in  the  head  and  neck. 

The  valves  are  applied  against  the  parietes  of  the  veins, 
when  the  course  of  the  blood  is  free  and  easy,  but  when  it 
meets  with  obstacles  in  its  passage,  the  valves  separate  from 
the  walls,  close  the  vein,  sustain  the  blood,  and  prevent  its 
reflux  towards  the  capillary  vessels. 


OP  THE  VEINS.  299 

§  447.  The  veins,  like  all  the  vessels,  are  surrounded  by  the 
cellular  tissue  of  the  parts  in  which  they  are  situated,  which 
forms  a  sheath,  loose  around  the  trunks,  but  more  intimately 
united  with  the  twigs.  The  sheath  of  the  vena  porta  is  re- 
markable in  the  liver,  where  it  is  known  under  the  name  of 
capsule  of  Glisson. 

The  outer  membrane,  properly  so  called,  is  thinner  and  less 
condensed  than  that  of  the  arteries,  to  which  it  bears  a  great  re- 
semblance. The  inner  membrane  is  formed  of  fibres  more  ex- 
tensible and  softer  than  those  of  the  arteries.  These  fibres  appear 
nearly  all  longitudinal,  when  the  membrane  is  examined  and 
held  between  the  eye  and  the  light;  some  of  the  most  inter- 
nal fibres  seem  annular;  but  when  we  wish  to  separate  the 
fibres  of  this  membrane,  the  same  difficulty  is  experienced  in 
all  directions.  In  the  human  species  this  membrane  is  much 
thicker  in  the  system  of  the  inferior  vena  cava  than  in  the 
other;  generally  it  is  also  thicker  in  the  superficial  than  in 
the  deep  seated  veins;  thus  the  internal  saphenavein  has  very 
thick  parietes  at  the  lower  part  of  the  leg.  Near  their  en- 
trance into  the  heart,  the  veins  have  distinct  muscular  fibres. 
The  inner  membrane,  which  is  thin  and  transparent,  differs 
from  that  of  the  arteries  by  its  extensibility  and  its  resistance 
to  rupture,  and  by  its  filamentous  texture,  which  becomes  evi- 
dent when  it  is  distended  and  torn.  The  large  veins  of  the 
cranium  or  sinuses,  the  veins  of  the  bones  and  some  others, 
are  almost  entirely  constituted  by  the  inner  membrane,  and 
are  besides,  as  it  were,  scooped  out  in  the  substance  of  the  dura 
mater,  the  bones,  &c. 

The  parietes  of  the  veins  are  provided  with  small  blood 
vessels  and  nervous  filaments,  which  may  be  followed  for  a 
certain  extent. 

§448.  The  parietes  of  the  veins  are  whitish,  semi-transpa- 
rent, thinner  than  those  of  the  arteries;  generally  their  thick- 
ness augments  absolutely  from  the  roots  towards  the  trunks, 
and  diminishes,  when  compared  with  the  diameter,  by  follow- 
ing the  same  course.  Their  density  is  of  115  or  110;  the 
firmness  of  their  walls  is  much  less  than  that  of  the  arteries, 
for  this  reason  they  collapse  when  empty,  with  the  exception 


300  GENERAL   ANATOMY. 

of  those  of  the  uterus,  the  liver,  &c.  which  are  attached  to  the 
suhstance  of  the  organs.  They  are  less  extensible  in  the  lon- 
gitudinal direction  than  the  arteries,  but  much  more  so  in  the 
circular.  Since  Wintringham's  experiments,  it  is  generally 
admitted  that  the  veins  oppose  a  much  greater  force  to  the 
causes  of  rupture  than  the  arteries;  on  the  other  hand,  they 
not  only  yield  much  more  to  distention,  but  also  tear  across, 
much  more  frequently  than  the  arteries,  while,  on  the  con- 
trary, they  have  appeared  to  me  to  resist  greater  distention 
longitudinally.  The  parietes  of  the  veins  are  very  elastic, 
but  less  so  than  those  of  the  arteries.  Their  irritability  or 
vital  contractility  is,  on  the  contrary,  greater  than  that  of  the 
arteries,  but  less  than  that  of  the  capillaries.  It  has  been  de- 
nied by  several  physiologists,  but  proved  by  many  experi- 
ments. It  is  sufficient  to  have  observed  the  effect  of  local 
cold  on  the  subcutaneous  veins,  and  to  know  that  the  portion 
of  a  vein  between  two  ligatures,  when  punctured,  empties  it- 
self entirely  and  rapidly  in  a  living  animal,  while  this  does 
not  occur  after  death,  to  admit  the  existence  of  irritability  in 
the  veins.  Their  sensibility  is  obscure  or  doubtful;  Monro, 
in  his  lectures,  affirmed  that  he  had  felt  the  puncture  of  a  de- 
nuded vein.  The  force  of  formation  of  the  veins  is  not  less 
evident  than  that  of  the  arteries. 

§449.  The  function  of  the  veins  is  to  convey  the  blood 
from  every  part  of  the  body  to  the  heart.  We  have  seen  that 
each  contraction  of  the  ventricles  determines  an  augmentation 
of  the  continuous  movement  of  the  blood  in  the  arteries;  this 
augmentation  goes  on  diminishing  in  the  same  degree  as  the 
vessels  become  capillary.  In  these  latter,  as  well  as  in  the 
veins  generally,  the  movement  is  uniform.  The  blood  in  the 
veins  is  animated  by  the  movement  imparted  to  it  by  the 
heart,  the  arteries,  and  by  the  capillary  vessels.  Do  the  veins 
exercise  an  additional  action?  This  is  not  doubtful;  let  any 
one  compress  or  tie  the  artery  of  a  member  in  an  animal,  the 
flow  of  the  blood  in  the  veins  will  be  slower;  but  will  not  be 
for  this  stopped;  if  a  vein  be  tied,  it  will  however  empty  itself 
above  the  ligature,  it  empties  itself  even  between  two  liga- 
tures. To  the  causes  already  mentioned,  we  must  add  the 


OF  THE  VEINS.  301 

alternate  relaxation  of  the  heart,  which  produces  a  kind  of  at- 
traction; inspiration,  which  produces  a  still  more  powerful 
one,  and  the  compression  of  the  surrounding  muscles.  The 
valves,  by  dividing  the  column  of  the  blood,  render  these  di- 
verse powers  more  efficacious.  The  form  of  the  venous  sys- 
tem is  the  cause  that  the  movement  of  the  blood,  instead  of 
gradually  diminishing,  as  in  the  arteries,  is,  indeed,  slower 
than  these  latter,  the  capacity  of  which  is  less  than  that  of  the 
veins,  but  however,  go  on  accelerating  as  it  approaches  the 
heart.  The  venous  circulation  is  much  more  dependent  than 
the  arterial  on  the  effects  of  gravity  and  pressure. 

§450.  The  course  of  the  blood  in  the  veins  is  continuous, 
and  these  vessels  do  not  present  any  pulsations;  in  some 
places  and  under  certain  circumstances,  however,  they  present 
something  analogous  to  an  arterial  pulse,  which  for  this  reason 
is  called  venous  pulse.  In  the  neighbourhood  of  the  heart, 
the  venous  trunks,  which  are  deprived  of  valves,  experience 
alternately,  during  the  contraction  of  the  auricles,  a  reflux  of 
blood  which  makes  them  swell  out,  and  during  the  relaxation 
of  the  auricles  there  occurs  a  rapid  flux,  which  causes  the  veins 
to  be  depressed.  In  the  ordinary  and  regular  state  of  func- 
tions, this  double  movement  is  confined  to  the  vicinity  of  the 
heart  and  is  not  sensible;  but  when  the  circulation  is  em- 
harassed  it  extends  into  the  abdomen,  and  becomes  visible  in 
the  neck.  It  is  the  same  with  the  influence  of  the  motions  of 
respiration:  inspiration  accelerates  the  entrance  of  the  blood 
into  the  venae  cavae  and  their  auricle;  active  expiration,  dif- 
ficulty or  suspension  of  respiration,  and  efforts,  on  the  contra- 
ry, slacken  or  suspend  it;  in  the  ordinary  state,  these  effects  are 
little  appreciable  or  extended;  but  they  become  very  much 
so  in  the  opposite  cases.  The  efforts,  in  which  the  effects  of 
active  expiration  are  carried  to  the  highest  degree,  determine, 
in  a  very  sensible  manner,  the  stasis  of  the  venous  blood  in  the 
head,  the  abdomen,  and  gradually  even  as  far  as  the  limbs; 
while  it  is  to  the  contrary  effects  of  inspiration  on  venous  cir- 
culation, that  we  must  ascribe  death  by  the  introduction  of  air 
into  the  heart.  When,  in  fact,  by  an  operation  or  accident,  a 
large  vein  is  opened  at  the  base  of  the  neck  or  in  the  subcla- 


3t)2  GENERAL  ANATOMY. 

vian  region,  a  deep  inspiration  sometimes  draws  air  into  it, 
which  is  sucked  into  the  right  cavity  of  the  heart,  and  which, 
by  stopping  the  circulation,  produces  sudden  death. 

§  451.  In  youth  the  venous  system  is  less  extensive,  in  pro- 
portion to  the  arterial  system,  than  in  the  adult  age;  its  rela- 
tive capacity  continues  to  augment  in  old  age.  The  parietes 
of  the  veins  offer  small  observable  changes;  their  senile  ossi- 
fication is  extremely  rare. 

§  452.  The  morbid  alterations  of  the  veins,*  have  been  less 
studied  than  those  of  the  arteries. 

The  inflammation  of  the  veins  or  phlebites,  is  an  affection 
to  which  Hunter  has  been  one  of  the  first  to  draw  the  atten- 
tion of  the  profession.  It  ordinarily  occupies  a  considerable 
extent  of  the  veins,  and  generally  extends  towards  the  heart. 
It  often  gives  rise  to  the  formation  of  pus,  and  at  other  times 
to  that  of  plastic  matter  in  the  cavity  of  the  vein,  around  it, 
and  even  in  its  own  thickness.  It  mostly  depends  on  mecha- 
nical lesions. 

§  453.  Wounds  of  the  veins,  considered  under  an  anatomical 
point  of  view,  present  some  analogy  with  those  of  the  arteries; 
but,  in  whatever  mode  they  are  inflicted,  they  are  much  more 
easily  followed  by  ulceration  or  extension  and  often  suppura- 
tive  inflammation  than  those  of  the  arteries,  and  they  unite 
with  more  difficulty.  After  puncture  or  incision,  there  re- 
mains between  the  edges  a  space  filled  by  a  new  membrane; 
the  ligature  does  not  first  determine  the  division  of  the  inner 
membrane  and  quickly  its  adhesion,  but  this  membrane  is  at 
first  only  plaited,  and  is  divided  but  slowly  in  order  to  unite 
feebly. 

§  454.  Accidental  productions  are  more  rare  in  the  parietes 
of  the  veins  than  in  those  of  the  arteries.  The  cartilaginous, 
or  an  analogous  thickening,  occurs  however  sometimes  in  the 
parietes  of  the  veins  which  are  obliterated;  Morgagni  ob- 
served it  once  in  the  vena  cava.  Ossification  is  extremely 
rare  in  the  veins.  Dr.  Baillie  has  seen  it  once  to  occur  in  the 
vena  cava  inferior  near  the  iliacs,  and  Dr.  Macartney  once 

*  Hodgson*  op.  cit. — B.  Travers,  Surgical  Essays,  part  first. 


OF  THE  VEINS.  303 

in  the  external  vena  snphena  of  a  man  who  died  with  an  ulcer 
on  the  leg.  I  have  observed  that  the  parietes  of  the  veins  are 
thicker  on  the  side  which  touches  an  artery,  than  in  the  re- 
mainder of  their  circumference,  and  I  have  once  seen  in  an 
old  man  a  femoral  vein  ossified  on  the  side  next  to  the  artery, 
which  itself  was  ossified  throughout  its  circumference  and  for 
some  extent  of  its  length. 

Morbid  productions  are  sometimes  observed  under  the  form 
of  vegetation,  at  the  internal  surface  of  the  veins,  whether 
the  affected  vein  be  surrounded  by  similar  productions,  or 
not. 

§  455.  The  dilatation  of  the  veins  is  very  frequent,  and  is 
of  various  kinds;  sometimes  the  whole  venous  system  is  af- 
fected by  it;  very  often  dilatation  affects  one  or  some  veins 
only,  which  constitutes  varix.  Almost  every  part  of  the  body 
may  be  the  seat  of  it ;  however,  the  most  depending  parts  are 
those  most  subject  to  it,  as  the  inferior  limbs,  the  genital  or- 
gans and  the  anus;  it  is  also  the  most  superficial  veins,  as  the 
subcutaneous,  which  are  oftener  affected.  The  augmentation 
of  the  volume  is  not  only  in  the  circular  dimension,  but  vari- 
cose veins  form  a  great  many  flexuosities  which  are  ascribable 
to  the  increase  of  their  length.  Sometimes  dilatations  of  very 
little  extent,  and  confined  to  a  part  of  the  circumference  of 
the  vein  are  found,  either  alone,  or  together  with  more  gene- 
ral dilatations.  Varicose  aneurism  is  another  kind  of  dilata- 
tion depending  on  the  accidental  communication  of  an  artery 
and  a  vein,  and  on  the  passage  of  the  blood  from  the  former 
into  the  latter.  This  affection  is  commonly  accompanied  with 
a  remarkable  thickening  of  the  parietes  of  the  elongated  and 
dilated  vein.  Moreover  a  consecutive  aneurism  is  sometimes 
formed  between  the  two  vessels:  this  case  constitutes  the  va- 
ricose aneurism. 

§  456.  Veins  become  sometimes  narrow  in  consequence  of 
the  thickening  of  their  parietes;  they  are  sometimes  closed  by 
the  effect  of  plastic  inflammation;  sometimes  they  are  com- 
pressed by  neighbouring  tumours,  or  embraced  within  a  liga- 
ture. In  those  cases,  in  which  their  cavity  is  obliterated, 

and  in  which  circulation  no  longer  occurs,  the  blood  passes 
40 


304  GENERAL  ANATOMY. 

through  branches  and  anastomoses,  and  a  collateral  circulation 
is  established. 

The  inferior  vena  cava  has  been  found  obliterated,  either 
under,  or  even  on  a  level  with  the  subhepatic  veins,  and  the 
blood  passing  through  the  vena  azygos;  one  of  the  primitive 
iliac  veins,  one  of  the  jugular  veins,  &c.  have  been  several 
times  found  obliterated.  Four  times  I  have  seen  the  trunk  of 
the  crural  vein  obliterated  in  the  groin,  and  in  every  instance 
the  circulation  was  easily  carried  on  by  collateral  passages. 
Hunter  once  observed  the  superior  vena  cava  and  the  left 
bracio-cephalic  vein  almost  entirely  destroyed  by  the  pressure 
caused  by  an  aneurism.  I  have  seen  a  case,  however,  in  which 
the  superior  vena  cava  and  its  branches  were  filled  with 
plastic  matter,  and  impermeable  to  blood,  and  in  which  death 
appeared  to  have  been  the  result  of  this  alteration.  I  have 
remarked  several  times,  but  not  always,  great  serous  infiltra- 
tions coinciding  with  the  obliteration  of  the  veins. 

§457.  Small,  hard  and  round  bodies  are  sometimes  found 
in  the  veins,  which  on  a  superficial  observation  might  be  taken 
for  accidental  osseous  productions.  Some  writers  have  even 
supposed  that  they  were  at  first  formed  in  the  parietes  of  the 
veins,  in  the  edge  of  their  valves,  or  even  on  the  exterior  of 
these  vessels;  but  this  is  not  true.  They  are  concretions,  phle- 
bolites,  from  the  size  of  a  grain  of  millet  to  that  of  a  pea,  of 
various  consistence,  formed  of  superincumbent  layers,  inclosed 
in  the  coagulated  fibrinous  blood,  and  often  lodged  in  the  lateral 
dilatations  of  the  veins  where  the  blood  stagnates,  or  in  the 
varicose  veins,  and  always  in  the  depending  veins.  The  veins 
in  which  they  are,  in  fact,  most  commonly  met  with,  are  those 
of  the  anus,  the  neck  of  the  bladder,  the  uterus,  the  ovaries, 
the  testicles,  and  sometimes  even  the  subcutaneous  veins  of 
the  leg. 

The  hexathyridium  or  polystoma  venarum  of  which 
Treutler  found  two  in  the  ruptured  tibial  vein  of  a  man,  who 
had  been  washing  in  a  river,  seems  to  be  an  aquatic  worm,  a 
planaria,  which  had  found  its  way  in  it,  and  not  an  (ento- 
zoaire)  cntozoary. 


OF  THE  LYMPHATIC  VESSELS. 

SECTION  IV. 

OF  THE  LYMPHATIC  SYSTEM. 

§458.  The  lymphatic  system  comprehends,  1st:  the  vessels 
which  convey  the  lymph  and  chyle  into  the  veins,  and  2d 
enlargements  occurring  in  their  course,  and  which  are  called 
conglobate  glands,  or  lymphatic  ganglia. 

ARTICLE  I. 

OF  THE  LYMPHATIC  VESSELS. 

§459.  The  lymphatic  vessels,  called  also  absorbents,  are  so 
attenuated,  thin  and  valvular,  which  renders  their  observa- 
tion and  injection  very  difficult,  that  the  knowledge  of  their 
existence  is  rather  of  a  recent  date.  The  ancients,  however, 
had  a  glimspe  of  them.  Erasistratus  and  Erophilus  had  cer- 
tainly perceived  the  chyliferous  vessels.  It  is  Eustachio  who 
has  discovered  the  thoracic  canal  in  the  horse.  Aselli  saw 
and  called  lacteal  vessels,  the  chyliferous  vessels  of  some  ani- 
mals. He  points  out  very  well  their  functions.  Veslingius 
is  the  first  who  saw  the  chyliferous  or  lymphatic  vessel  of 
the  mesentery  and  thoracic  duct  in  man.  We  owe  to  0.  Rud- 
beck  the  discovery  of  the  vessels  of  this  kind  in  the  other 
parts  of  the  body,  although  it  has  also  been  ascribed  to  Th. 
Bartholin  and  to  Jolyf.  The  discoverer  gave  them  the  name 
of  serous,  aqueous,  or  lymphatic  vessels.  Bartholin  conjec- 
tured that  they  were,  like  the  veins,  continuous  with  the  ca- 
pillary arteries,  and  destined  to  convey  the  watery  part  of  the 
blood.  Ruysch  has  very  well  described  their  valves.  The 
knowledge  of  the  lymphatic  vessels  has  been  very  much  in- 
creased by  the  labours  of  Meckel,  Monro,  by  those  of  W. 
Hunter,  and  of  three  of  his  disciples,!.  Hunter,  W.  Hewson,* 

*  Descriptio  systematis  lyrnphatici,  ex  anglico  versa,  in  op.  omn.  Lugd- 
Bat  1795. 


306  GENERAL  ANATOMY. 

and  Cruikshank;*  especially  by  those  of  the  illustrious  P. 
Mascagni,t  and  by  some  other  writers,  J  all  of  whom  have 
ascribed  to  them  patulous  orifices,  and  absorption  to  these 
orifices. 

§  460.  These  vessels  are  commonly  distinguished  into  chy- 
liferous  and  lymphatic  vessels;  but  this  distinction  is  entirely 
superfluous  and  without  any  utility,  for  their  disposition,  their 
texture  and  their  functions  are  the  same. 

§  461.  The  lymphatic  vessels  have  an  arborescent  disposi- 
tion, like  other  vessels.  The  humours  which  they  contain, 
pass  through  them,  like  the  veins,  from  the  ramifications,  or 
rather  from  the  roots,  towards  the  trunks.  The  aggregate  of 
these  vessels  consists  in  a  principal  and  an  accessory  trunk, 
in  which  numberless  roots  terminate. 

§462.  Lymphatic  vessels  are  found  in  every  part  of  the 
body,  excepting  the  spinal  marrow,  the  brain,  the  eye  and  the 
placenta. 

Their  situation  is  remarkable,  that  in  the  limbs  and  in  the 
parietes  of  the  trunk,  they  are,  like  the  veins,  distributed  in 
two  plans,  the  one  superficial  or  subcutaneous,  the  other  in- 
termuscular  or  deep,  which  accompanies  the  blood-vessels  and 
nerves;  and  that  in  the  splanchnic  cavities  there  occurs,  also, 
a  plane  of  lymphatic  vessels,  situated  immediately  under  the 
serous  membranes,  and  others  more  deeply  seated. 

§  463.  The  number  of  lymphatic  vessels  is  very  considera- 
ble; as  many  as  twenty  are  counted  in  the  superficial  plane  of 
the  inferior  limbs  accompanying  the  inner  saphena  vein  alone, 
and  a  smaller,  but  still  considerable  number,  accompanies  the 
deep  seated  vessels.  The  superficial  lymphatic  vessels  are 

*  Anatomic  dcs  veisseaux  absorbans  da  corps  humain,  traduite  de  1'anglais 
par  Petit  Radel.  Paris,  1787. 

j-  Vasorum  lymphaticorum  corp.  hum.  historic,  d  ichonographia.  Senis, 
1787. 

^Luchvig,  a  German  translation  of  Cruikshank  and  ofMuscagnf,  with  ad- 
ditions. Lips.  1789. — Werner  and  Feller,  Vasorum  ladeorum  aiquc  lymph, 
anal,  physiol.  descriptio.  Lips.  1784. — J.  G.  Haase,  dc  vasis  cutis  et  inteslin. 
aljsnrbcnlibus,  &c.  Lips.  1786. — Schrcger,  FragntciUa  ana.  et  physiol. 
fane.  i.  Lips.  1791. 


OF  THE  LYMPHATIC  VESSELS.  307 

Jess  voluminous  than  the  deeply  seated  ones.  The  size  of 
these  vessels  is  much  less  than  that  of  the  veins.  Those  of 
the  inferior  extremities  are  larger  than  those  of  the  superior 
members,  those  of  the  head  are  very  small.  As  to  their  ag- 
gregate capacity,  it  has  not  been  accurately  determined;  it 
appears  generally  to  be  nearly  double  that  of  the  arteries,  and 
to  equal  that  of  the  veins  in  the  superficial  plane  at  least. 

§464.  The  origin  of  the  lymphatic  vessels  is  invisible  and  un- 
known. Physiological  considerations  and  anatomical  experi- 
ments have  caused  authors  first  to  admit  and  then  to  reject  their 
direct  and  immediate  continuation  with  the  arteries.  We  have 
also  seen  that  the  origin  admitted  to  take  place  by  open  orifices 
at  the  surface  of  the  two  tegumentary  and  serous  membranes, 
in  the  areolae  of  the  cellular  tissue,  and  in  the  substance  of  the 
organs,  which  has  been  deduced  from  considerations  and  ex- 
periments of  the  same  kind,  is  not  better  founded.  It  is  well 
to  know  how  to  doubt. 

§  465.  As  soon  as  they  can  be  perceived,  the  radicles  of  the 
lymphatic  vessels  are  seen  to  unite  together,  to  separate,  and 
unite  anew,  so  as  to  form  net-works  which  constitute  in  a 
great  measure  the  serous,  tegumentary  and  other  membranes. 

These  vessels  become  generally  larger  and  more  numerous 
as  they  are  farther  removed  from  their  origin.  In  their  course 
they  continue  to  divide  into  branches,  which  reunite  with 
other  neighbouring  branches,  or  even  with  each  other,  so  as 
to  form  parts  entirely  surrounded  by  liquid.  These  divisions 
and  these  numerous  anastomoses  form  plexuses  in  many 
places. 

When  they  are  full  and  a  little  distended  they  appear  rather 
moniliform  than  cylindrical.  This  appearance  of  a  rosary  is 
owing  to  the  great  number  of  valves  with  which  they  are  pro- 
vided, and  to  the  dilatation  which  they  present  above  them. 
They  also  frequently  present  ovoid  dilatations.  We  observe 
in  them  many  variations  in  their  course:  those  of  one  side  al- 
ways differ  more  or  less  from  those  of  the  other. 

All  the  lymphatic  vessels,  after  a  longer  or  shorter  course, 
ramify  in  the  same  manner  as  the  arteries,  and  seem  to  ter- 
minate in  lymphatic  glands,  beyond  which  they  reappear  again 


308  GENERAL  ANATOMY. 

formed  of  roots,  which  collect  themselves  in  the  manner  of 
veins.  In  those  of  the  members,  for  the  distance  of  several 
feet,  there  are  no  interruptions  of  this  kind;  in  those  of  the 
mesenteiy,  every  few  lines  there  are  glands.  Some  pass  along 
side  of  a  gland  without  entering  it.  It  would  even  appear, 
according  to  Cruikshank,  that  the  lymphatic  vessels  of  the 
back  arrive  at  the  trunk  without  meeting  any  glands;  but 
Mascagni,  whose  authority  in  these  matters  is  so  great,  assures 
us  that  no  lymphatic  vessel  reaches  the  trunk,  unless  it  has 
passed  at  least  through  one  gland. 

§466.  After  a  course  more  or  less  long,  more  or  less  inter- 
rupted by  ganglions,  the  lymphatic  vessels  of  the  inferior  half 
and  of  the  superior  and  left  quarter  of  the  body,  terminate  by 
a  very  elongated  trunk,  the  thoracic  duct,  into  the  left  subcla- 
vian  vein;  the  others  terminate  by  a  very  short  trunk  in  the 
other  subclavian  vein.  These  modes  of  terminations  are  them- 
selves subject  to  different  variations.  Does  there  exist  other 
terminations  of  the  lymphatic  vessels  in  the  veins?  A  part  of 
this  query  must  be  examined  here,  and  the  other  when  we 
shall  speak  of  the  lymphatic  ganglia. 

Several  anatomists  and  physiologists  have  admitted  this 
opinion,*  which  may  be  founded  on  the  circumstances  that 
every  where,  and  especially  in  the  mesentery,  the  known  ra- 
dicles of  the  lymphatic  vessels  have  a  capacity  much  greater 
than  that  of  the  vessels  which  form  their  continuation;  on  the 
circumstance  that  in  this  part  of  the  body,  also,  there  is  often 
found  in  the  veins,  as  in  the  lymphatic  vessels,  substances  in- 
troduced by  absorption,  and  even  those  which  have  been 
directly  injected  into  these  latter  vessels;  and  finally,  on 
the  circumstance  that  the  mere  tying  of  the  thoracic  duct, 
causes  death  only  after  ten  or  fifteen  days,  and  that  the  sub- 
stances introduced  into  the  intestines,  and  absorbed  by  its  in- 
ternal membrane,  arc  then  found  in  the  blood.  But  this  com- 
munication has  never  been  seen,  nor  is  it  generally  admitted. 
It  would  appear  to  be  especially  in  the  lymphatic  glands 
that  it  occurs;  but  we  shall  revert  to  this  subject  hereafter, 
(art.  ii. ) 

*  See  Ludwig,  be.  cit. 


OP  THE  LYMPHATIC  VESSELS.  309 

§  467.  The  surfaces  of  the  lymphatic  vessels,  like  those  of 
all  the  vessels,  are  the  one  cellular  and  adherent,  the  other 
smooth  and  free:  the  latter  presents  a  multitude  of  valves. 

These  valves,  which  are  of  a  semilunar  or  parabolic  form, 
are  mostly  arranged  in  pairs,  and  are  large  enough  to  close 
tho  vessel  completely.  They  are  generally  placed  at  unequal 
intervals,  excepting  in  the  vessels  of  the  testicles,  where  they 
occur  nearly  every  line,  which  gives  them  more  than  any 
other  the  appearance  of  a  chaplet.  They  are  more  or  less 
close,  according  to  the  parts,  without  their  being  more  parti- 
cularly so  in  the  branches  than  in  the  twigs;  in  certain  vessels 
there  occurs  spaces  of  several  inches  without  valves:  the 
thoracic  duct  is  especially  remarkable  in  this  respect.  In 
some  points  the  insertion  of  a  small  vessel  in  a  larger  one  is 
only  furnished  with  a  single  valve.  In  some  places  of  the 
trunks  annular  valves,  that  do  not  entirely  close  the  canal,  are 
found.  The  insertion  of  the  trunks  into  the  subclavian  veins 
is  furnished  with  a  double  valve,  which  effectually  prevents 
the  reflux  of  the  blood  from  entering  into  their  cavity.  All 
these  valves,  like  those  of  the  veins  and  arteries,  are  formed 
of  a  duplicature  of  the  inner  membrane. 

§  468.  Lymphatic  vessels  are  formed  of  two  membranes, 
very  distinct  in  their  principal  trunks. 

The  external,  cellular  and  unequal  or  exterior  is  united  to 
the  surrounding  cellular  tissue,  which  invests  it  with  a  sheath; 
more  deeply,  it  is  distinctly  fibrous  or  filamentous:  it  is  even 
supposed  that  muscular  fibres  have  been  observed  in  it.  The 
inner  membrane  is  very  thin. 

Small  sanguineous  vessels,  arteries  and  veins,  have  been  fol- 
lowed up  into  the  thickness  of  the  outer  membrane;  some  say 
that  they  have  also  seen  in  it  lymphatic  vessels.  No  one  has 
ever  been  able  to  perceives  nerves  in  them. 

§  469.  The  parietes  of  the  lymphatic  vessels,  although  very 
thin  and  transparent,  are  dense  and  very  resistant,  much  more 
so  than  those  of  the  veins,  taking  into  consideration  the  differ- 
ence of  their  thickness.  Nevertheless,  these  vessels  are  exten- 
sible, and  also  very  retractile.  Elasticity  is  manifest  in  them: 


310  GENERAL  ANATOMY. 

if  they  are  filled  and  distended  in  the  subject,  the  matter  which 
is  introduced  into  them,  is  rejected. 

Vital  irritability  or  contractility*  is  no  less  evident  in  them: 
although  Mascagni  and  several  others  have  denied  it.  If  they 
be  exposed  to  the  air  in  a  living  subject,  they  manifestly  con- 
tract; if  the  thoracic  duct  or  any  other  lymphatic  vessel  be 
punctured  after  being  tied,  the  liquid  issues  by  jets,  like  the 
blood  which  comes  from  a  vein,  while  after  death,  it  only 
escapes  in  a  sheet  over  the  lips  of  the  wound.  It  is  true  that 
mechanical  or  chemical  irritations  do  not  produce  movements 
similar  to  those  of  the  muscles,  but  we  must  observe  that  irri- 
tability varies  according  to  the  organs.  • 

We  know  nothing  concerning  their  sensibility,  and  little 
about  their  force  of  formation. 

§  470.  The  lymphatic  vessels  contain  the  chyle  and  lymph 
[79];  they  convey  these  humours  from  their  radicles  to  their 
trunk,  which  is  very  well  proved  by  the  arrangement  of  their 
valves,  which  permits  the  fluid  to  flow  in  that  direction,  but 
prevents  it  in  an  opposite  one;  by  the  effects  of  the  ligature, 
below  which  they  swell  while  they  empty  themselves  above; 
and  by  the  valves  which  are  placed  at  their  insertion  in  the 
veins.  The  passage  of  the  liquids  through  them  is  slow  and 
uniform,  that  is  to  say,  they  do  not  present  any  pulsation. 

Darwin,  Thilow  and  others,  in  order  to  explain  the  rapidity 
of  certain  secretions,  have  admitted  a  retrograde  movement  of 
the  humours  in  the  lymphatic  vessels:  in  such  a  manner,  for 
instance,  that  the  liquid  absorbed  by  the  parietes  of  the  sto- 
mach should  be  directly  conveyed  by  the  lymphatic  vessels, 
and  by  means  of  their  communications  to  the  kidneys,  and 
hence  to  the  bladder.  This  would  be  to  admit  that  the  valves 
do  not  present  a  very  great  obstacle  to  the  retrograde  motion 
of  the  liquids.  But  it  is  certain,  on  the  contrary,  that  the 
valves  oppose  an  insurmountable  obstacle  to  the  return  of  the 
liquids;  and  moreover,  observations  and  direct  experiments 
cause  us  to  discover  in  the  urinary  passages  substances  intro- 

*  Schreger,  de  Irritabilltate  vasomm  lymphaticorurn.     Lips.  1789. 


OF  THE  LYMPHATIC  GANGLIA.  311 

duced  into  the  stomach,  without  the  intermediate  lymphatic 
vessels  presenting  the  smallest  evidence  of  their  passage. 


ARTICLE  II. 
OF  THE  LYMPHATIC  GANGL-IA. 

§  471.  The  conglobate  or  ovoid  glands,  which  interrupt  the 
continuity  of  the  lymphatic  vessels,  stand  in  the  same  rela- 
tion with  respect  to  these  vessels,  as  the  nervous  ganglia  to 
the  nerves. 

The  ganglia  were  very  anciently  known.  It  is  partly  of 
them  that  Hippocrates  speaks  under  the  name  of  glands.  Fr. 
Sylvius  has  given  to  them  the  epithet  of  conglobate*  and  Los- 
sius  that  of  lymphatic  glands.  According  to  the  comparison 
above  mentioned  and  made  by  Soemmering,  and  to  avoid  con- 
fusion, M.  Chaussier  has  designated  them  under  the  name  of 
lymphatic  ganglions. 

§  472.  They  are  situated  in  the  course  of  all  the  lymphatic 
vessels,  beginning  at  the  instep  and  at  the  fold  of  the  arm,  at 
the  elbow  for  the  members,  at  the  carotid  canal  and  at  the  ex- 
terior base  of  the  cranium  for  the  head.  Many  of  them  exist 
in  the  neck,  in  the  arm-pit,  in  the  groin,  several  in  the  ante- 
rior parietes  of  the  thorax  and  abdomen,  and  a  very  great 
number  in  these  cavities.  They  exist  especially  very  abun- 
dantly about  the  roots  of  the  lungs  and  in  the  mesentery,  near 
parts,  consequently,  which  admit  much  extraneous  matter. 
None  are  known  to  exist  in  the  cranium  or  in  the  spine. 

Their  size  varies,  in  the  healthy  state,  from  that  of  a  lentil 
to  that  of  an  almond.  Generally,  the  smallest  are  situated 
towards  the  origin  of  the  vessels,  and  the  largest  towards  their 
trunks.  The  most  voluminous  and  closest  to  each  other  are 
formed  towards  the  root  of  the  mesentery,  the  smallest  in  the 
epiploon;  those  of  the  head  and  arms  are  small. 

Their  figure  is  rounded,  oblong  and  a  little  flattened;  they 
are  more  or  less  unequal  at  the  surface;  they  generally  have 
the  form  of  an  almond. 
41 


312  GENERAL  ANATOMY. 

The  lymphatic  ganglia  are  generally  of  a  reddish  white,  si- 
milar to  flesh,  but  their  colour  varies  according  to  the  regions 
they  occupy;  thus  those  which  are  subcutaneous  have  a  deeper 
colour;  those  in  the  environs  of  the  liver  are  yellowish,  those 
of  the  spleen  brown,  those  of  the  lungs  blackish,  those  of  the 
mesentery  very  white,  &c. 

Their  consistence  is  greater  than  that  of  any  soft  part. 

§473.  The  lymphatic  ganglions  are  enveloped  in  a  thin 
fibrous,  very  vascular,  membrane,  united  to  the  surrounding 
cellular  tissue,  and  which  sends  fine  and  soft  prolongations 
into  the  interior. 

The  lymphatics,  whose  course  is  interrupted  by  glands,  are 
distinguished  into  those  which  come  to  these  glands,  vasa  in- 
ferentict)  and  in  those  that  issue  from  them,  vasa  efferentia'. 
they  are  distinguished  from  each  other  by  the  direction  of 
their  valves.  The  number  of  vasa  inferentia  is  very  varia- 
ble, they  may  be  from  one  to  twenty  or  thirty;  that  of  the 
vasa  efferentia  is  also  variable,  seldom  correspondent,  and 
ordinarily  fewer.  The  first  mentioned  enter  the  gland  on  the 
side  nearest  to  the  origin  of  the  system,  the  others  issue  from 
the  opposite  extremity,  which  corresponds  to  the  trunks.  The 
vasa  inferentia,  in  approaching  the  gland,  divide  themselves 
into  twigs,  which  go  off  radiating  around  it,  divide  and  sub- 
divide themselves  at  its  surface,  so  as  to  surround  it  with  a 
net-work.  The  vasa  efferentia  produce  nearly  the  same  effect 
at  the  other  extremity  of  the  gland,  by  the  successive  reunion  of 
their  radicles  and  of  their  roots  in  trunks  more  or  less  numer- 
ous and  voluminous.  The  total  capacity  of  the  vasa  efferentia 
seems  generally  smaller  than  that  of  the  vasa  inferentia;  this 
is  particularly  obvious  in  the  mesentery. 

The  lymphatic  glands  have  also  remarkable  sanguineous 
vessels.  The  arteries  are  sufficiently  numerous  and  volumin- 
ous, so  that  when  injected,  the  glands  are  entirely  coloured  by 
it.  The  veins,  still  more  voluminous  than  the  arteries,  are 
deprived  of  valves.  Nervous  filaments  may  be  seen  reaching 
these  organs  and  transverse  them;  but  it  is  very  difficult  to 
ascertain  whether  some  filaments  terminate  in  them,  or  whe- 
ther they  are  merely  crossed  by  them  all.  Two  great  anato- 


OF  THE  LYMPHATIC  GANGLIA.  313 

mists  entertain  opposite  opinions  on  this  subject:  Wrisberg 
admits  them,  and  Walter  rejects  them. 

§  474.  Anatomists  do  not  agree  any  better  with  reference 
to  the  internal  conformation  and  the  texture  of  the  lymphatic 
glands.  Albinus,  Ludwig,  Hewson,  Wrisberg,  Monro,  and 
Meckel,  consider  their  tissue  as  entirely  vascular;  Malpighi, 
Nuck,  Mylius,  Hunter  and  Cruikshank,  admit  of  cells  in  them; 
Scemmering  admits  these  two  kinds  of  texture,  and  a  third 
resulting  from  their  combination.  The  examination  I  have 
made  myself  of  this  tissue  in  man,  in  several  animals,  and 
especially  in  the  inguinal  glands  of  cows  which  died  during 
lactation,  has  shown  me  that  it  results  entirely  from  vessels, 
but  which  present  an  erectile  disposition  more  or  less  obvious. 
In  fact,  among  the  vasa  inferentia  which  penetrate  into  the 
thickness  of  the  gland,  some  acquire  and  preserve  a  great 
tenuity,  others  dilate  in  cells  like  the  veins  of  the  penis,  both 
having  numerous  anastomosing  communications.  The  roots 
of  the  vasa  efferentia  present,  on  the  other  hand,  the  same 
disposition,  that  is  to  say,  that  some  are  fine  radicles,  and  the 
other  roots  swelled  or  dilated  in  cells.  The  greater  number 
of  the  lymphatic  glands  present  in  their  interior  this  mixture 
of  minute  ramifications  and  enlarged  parts.  Some  only  pre- 
sent twigs  dilated  in  cells;  some  others,  seem  to  consist  only 
in  a  net-work  of  fine  ramifications.  It  is  by  these  varieties 
that  we  may  explain  the  diversity  of  opinions  which  has  ex- 
isted on  this  point  of  anatomy. 

The  lymphatic  glands  contain  in  their  interior  a  cream-like 
substance,  which  appears  to  be  contained  in  the  fine  or  large 
vessels  which  compose  them,  and  not  in  the  cellular  tissue. 

§475.  These  ganglia  are  more  voluminous,  softer,  more 
reddish,  and  contain  more  liquid  in  children  and  young  sub- 
jects than  in  adults;  they  greatly  diminish,  but  do  not  dis- 
appear in  old  age.  There  is  no  well  marked  difference  in 
this  respect  between  the  two  sexes.  Hewson  says  that  they 
are  larger  in  man:  Bichat  says,  however,  exactly  the  reverse. 
Under  the  skin  of  negroes  they  are  found  black. 

§  476.  The  function  ascribed  to  the  lymphatic  glands  is, 
that  they  serve  to  mix  the  liquids  arriving  by  the  different 


314  GENERAL  ANATOMY. 

vasa  inferentia,  and  to  the  elaboration  of  the  lymph  and  chyle. 
The  liquids  are  afterwards  conveyed  away  by  the  vasa  efferen- 
tia,  and  perhaps  in  part  also  by  the  veins.  This  point  has 
been  denied  by  many  celebrated  anatomists  and  physiologists, 
such  as  Haller,  Cruikshank,  Hewson,  Mascagni,  Soemmer- 
ing,  &c.;  but  it  is  to  be  feared  that  the  authority  of  these  great 
men,  may  have  caused  a  truth  to  be  rejected,  without  previ- 
ous examination. 

Besides  the  facts  already  related  favouring  the  opinion  in 
question,  we  may  remark  that  many  observers  have  perceived 
striae  of  chyle  in  the  vena  porta;  we  may  add  that  a  great 
many  anatomists  have  seen  and  I  have  often  seen,  the  mercury 
introduced  into  the  lymphatic  vessels  of  the  mesentery,  pass 
beyond  a  gland,  both  in  the  vasa  efferentia  and  in  the  veins  of 
the  gland;  now  this  passage  is  too  easy  and  too  constant  to  de- 
pend on  a  double  rupture,  and  not  to  a  natural  communication 
of  the  lymphatic  vessels  and  veins. 

§  477.  Besides  the  lesions  of  the  glands  and  lymphatic  ves- 
sels,* such  as  the  inflammation  of  both,  the  wounds  and  rup- 
tures of  the  vessels,  their  varicose  dilatation,  their  narrowing 
and  obliteration,  tubercles  and  other  morbid  productions  in 
the  glands,  &c.  authors  have  caused  the  lymphatic  system  to 
play  a  very  great  and  indeed  exaggerated  part  in  most  dis- 
eases, by  considering  it  as  an  apparatus  of  absorption. 

*  S.  Th.  Soemmering,  de  morbis  vasorum  absorbentium  corp.  hum.  in  8vo. 
Traj.  ad  Mcen.  1795. 


OF  THE  GLANDS.  315 


CHAPTER  V. 


OP  THE  GLANDS. 

§  478.  The  name  of  gland,*  glandula,  oS^u,  is  derived,  ac- 
cording to  Nuck,  from  the  similitude  the  ancients  thought  to 
perceive  between  the  lymphatic  ganglions  or  glands,  and  the 
fruit  of  the  oak. 

Objects  so  different  have  been  comprised  under  the  name  of 
gland,  that  much  difficulty  is  experienced  in  defining  it. 

Hippocrates  had  announced  that  the  glands  were  formed  of 
a  peculiar  granular  and  spongy  flesh,  not  dense,  having  the 
colour  of  fat,  the  consistence  of  wool,  easily  mashed  between, 
the  fingers,  provided  with  numerous  veins,  and  when  cut 
emitting  whitish  and  serous  blood.  He  comprehended  many 
parts  under  this  name,  and  especially  the  brain. 

Anatomists  for  a  long  time  also  had  a  vague  idea  of  the 
glands,  they  have  ascribed  to  them  a  rounded  form;  they 
then  have  comprehended  with  the  glands  and  the  vascular 
ganglions,  the  pineal  gland,  and  hypophysis  of  the  brain,  the 
synovial  adipose  bodies,  and  even  the  tongue. 

Another  definition,  founded  on  the  texture,  and  in  which 
there  entered  the  idea  of  a  mass  of  follicles  or  an  aggregate  of 

*  Warton,  adenographia.  Lond.  1656. — M.  Malpighi,  de  viscerum  strue- 
turdy  in  op.  omn.  et  de  struct.  glanduL  eonglob.  6?e.  in  op.  posth. — Lossius 
and  Pielow,  JDisq.  de  glandulis  in  Genere.  Viteb.  1683. — A.  Nuck,  Adeno- 
graphia curiosa.  L.  B.  1691. — G.  Mylius,  de  glandulis.  L.  B.  1698 — L. 
Terraneus,  de  Glandu.  universim,  &c.  L.  B.  1729. — Boerhaave  and  Ruysch, 
de  Fabrica  glandular,  &c.  in  Ruyschu  op.  omn. — A.  L.  de  Hugo,  comment,  de 
glandulis  in  genere,  &c.  Gotting.  1746.— Th.  de  Bordeu,  Recherches  ana- 
torn,  sur  les  glandcs,  6fc.  Paris,  1751. — G.  A.  Haase,  de  glandularum  de/i- 
nitionc.  Lips.  1804. — Leonhardi,  op.  cit. 


316  GENERAL  ANATOMY. 

vessels  with  a  peculiar  membranous  envelope,  still  compre- 
hended many  different  parts,  and  supposed  an  exact  know- 
ledge of  the  intimate  texture. 

It  has  also  been  attempted  to  define  the  glands  by  their  func- 
tion, by  saying  that  they  are  secreting  organs;  but  by  after- 
wards confounding  nutrition  and  secretion,  the  greater  number 
of  the  organs  were  included  in  this  definition;  or  by  distinguish- 
ing these  functions  from  each  other,  but  not  separating  intrinsic 
from  excretory  secretions,  the  serous  and  synovial  membranes 
were  confounded  with  the  glands. 

In  order  to  distinguish  the  glands  from  all  other  parts  ana- 
logous to  them  in  form,  in  apparent  texture,  and  even  to 
a  certain  extent  in  functions,  we  must  take  particular  notice 
of  their  connexions;  Bichat  and  Chaussier  have  taken  this 
consideration  for  the  basis  of  a  definition  of  the  glands;  Haase 
has  likewise  adopted  it;  but  he  has  supposed  excretory  ducts 
to  the  vascular  ganglions.  The  glands  are  organs  of  an  ob- 
round  lobular  form,  surrounded  with  membranes,  having  many 
vessels  and  nerves,  and  provided  with  ramified  excretory 
canals  which  terminate  at  the  surface  of  the  tegumentary 
membranes  and  pour  out  a  secreted  liquid.  Finally,  these 
are  the  organs  of  extrinsic  secretions  furnished  with  excreto- 
ry ducts. 

§  479.  The  glands,  when  thus  considered,  are  mere  appen- 
dages or  prolongations  of  the  tegumentary  membranes.  In 
animals  provided  with  vessels  and  a  heart,  the  only  ones  which 
have  massive  glands,  they  result  from  the  intimate  reunion  of 
these  two  kinds  of  organs:  this  is  the  reason  why  their  de- 
scription is  placed  here.  They  belong,  however,  more  to  the 
tegumentary  than  to  the  vascular  system,  for  in  animals  de- 
prived of  vessels,  glands  exist,  but  in  a  rudimentary  state; 
the  liver,  the  most  constant  of  all  the  glands,  the  kidneys  ex- 
cepted,  exists,  in  fact,  in  insects  under  the  form  of  a  ramified 
excretory  canal,  terminating  in  the  intestinal  tube,  but  floating 
and  free  in  the  abdomen. 

§480.  It  is  also  pretty  difficult,  and  perhaps  impossible,  to 
establish  a  well  marked  line  of  distinction  between  the  folli- 
cles or  crypta?  and  the  glands. 


OP  THE  GLANDS.  317 

We  have  already  stated,  that  among  the  follicles  some  were 
simple  and  solitary,  others  are  grouped,  collected  or  aggre- 
gated, others  again  are  composed  either  by  their  reunion  in  a 
common  orifice  or  lacuna,  or  at  the  same  time  by  the  agglo- 
meration of  several  follicles,  or  finally  by  a  common  and  rami- 
fied excretory  canal.  Here  a  difficulty  presents  itself,  for 
there  is  no  good  reason  why  the  amygdales  which  have  com- 
pound lacunae,  the  molar  glands,  the  prostate  and  Cowper's 
glands,  which  have  ramified  ducts,  should  not  be  classed 
among  the  glands,  as  well  as  the  sublingual,  the  lachrymal 
glands,  &c. 

The  most  perfect  and  least  equivocal  glands  are:  the  lachry- 
mal, the  salivary,  three  in  number  on  each  side,  viz.  the  pa- 
rotid, the  maxillary  and  sublingual ;  the  pancreas,  the  liverr 
the  kidneys,  the  testicles  and  mammae.  The  ovaries  like  the 
testicles  must  be  classed  with  this  kind  of  organs. 

§481.  The  form  of  the  glands  is  irregularly  round,  and 
present  a  great  variety.  Some  are  single,  like  the  liver  and 
pancreas,  not  symmetrical;  others  are  double  and  very  nearly 
alike  on  both  sides. 

§  482.  They  are  all  situated  at  the  trunk,  and  all,  whatever 
may  be  the  apparent  diversity  of  their  situation,  terminate  by 
their  ducts  in  the  mucous  membrane  or  in  the  skin. 

§483.  Their  size  differs  greatly:  the  liver  is  one  of  the 
most  voluminous  organs  of  the  body,  and  on  the  other  hand, 
the  lachrymal  and  sublingual  glands  and  the  ovaries  are 
scarcely  half  the  size  of  the  thumb. 

§  484.  In  their  interior,  some  are  lobed  and  lobulated  like 
the  lachrymal  and  salivary  glands  and  the  pancreas;  the  mam- 
ma3  are  less  distinctly  so;  the  testicles  are  so  in  another  man- 
ner; the  kidneys  are  only  so  in  the  foetus;  the  liver  is  only 
lobed  externally. 

In  the  former,  the  lobules  seem  to  be  formed  of  very  small 
particles,  but  similar  and  whitish;  in  the  liver  and  kidneys, 
we  find  two  substances  of  different  colour,  arranged  in  layers 
in  the  kidneys,  and  mixed  in  the  manner  of  fine  granite  in  the 
liver. 

§  485.  The  greater  number  of  glands  are  enveloped  with  a 


318  GENERAL  ANATOMY. 

cellular  membrane,  and  some  with  a  fibrous  one,  some  of 
which  are  surrounded  by  a  serous  membrane,  and  others  by  a 
great  deal  of  cellular  and  adipose  tissues.  The  internal  face  of 
this  membrane  is  continuous  with  the  cellular  tissue,  more  or 
less  loose,  which  exists  abundantly  in  the  glands. 

These  organs  have  many  sanguineous  and  lymphatic  vessels, 
and  few  nerves:  more,  however,  than  the  mucous  membrane 
generally,  but  less  than  the  skin.  The  greater  number  re- 
ceive only  arterial  blood ;  the  liver  alone  in  man  and  the  maYn- 
miferous  animals,  the  liver  and  kidneys  in  oviparous  animals, 
receive  venous  blood  besides,  which  explains  the  nature  of 
the  liquids,  so  different  from  the  blood,  and  altogether  excre- 
tory, furnished  by  these  glands.  The  number  and  volume,  or 
the  total  capacity  of  the  arteries,  are  very  different  in  the 
glands,  but  nowhere  greater  than  in  the  kidneys.  The  length, 
course  and  mode  of  distribution  of  the  vessels  are  also  very 
various.  The  difference  of  capacity  between  the  arteries  and 
veins  is  very  little  discernible  in  the  glands;  and,  in  fact,  the 
greater  part  of  the  blood  in  them  is  transformed  into  secreted 
humour,  and  conveyed  away  by  the  excretory  canals. 

§  486.  These  ducts  commence  by  very  fine,  invisible,  and 
probably  closed  radicles,  which  unite  with  each  other  in  the 
manner  of  the  veins,  to  form  several  trunks,  as  in  the  lachry- 
mal, sublingual  and  mammary  glands,  or  one  alone,  as  in  all 
the  other  glands  besides.  These  canals,  either  many,  or  single 
for  each  gland,  generally  take  a  straight  course,  in  the  testicles 
excepted,  where  it  is  tortuous,  and  terminate  on  the  tegu- 
mentary  membranes.  That  of  the  ovary  is  alone  interrupted; 
those  of  the  rnammse  present,  before  their  termination,  oval 
enlargements;  those  of  the  kidneys  present  at  first  an  enlarge- 
ment or  pelvis,  and  then  terminate  in  a  single  bladder  for 
both;  that  of  the  liver  and  that  of  each  testicle  have  also  a  re- 
servoir, but  situated  laterally,  and  to  reach  which  the  secreted 
liquid  is  obliged  to  take  a  retrograde  course.  The  canals  of 
the  other  glands  present  neither  interruption,  enlargements, 
nor  reservoirs. 

The  composition  of  the  excretory  ducts  is  always  the  re- 
sult of  a  mucous  membrane  whose  thickness  diminishes  in 


OF  THE  GLANDS.  319 

proportion  as  it  divides  in  more  minute  ramifications  in  the 
glands.  This  membrane  is  invested  externally  by  cellular 
tissue,  and  by  an  elastic  tissue;  in  some  ducts  by  an  erectile 
one,  as  in  the  urethra,  in  the  nipple,  and  perhaps  in  some 
others;  in  some  parts  of  the  excretory  passages,  the  mucous 
membrane  contains  muscular  fibres. 

§  487.  The  intimate  texture  of  the  glands  is  little  known. 
Malpighi  had  advanced  that  each  of  the  glandular  grains,  the 
acini,  ought  to  be  considered  as  a  follicle,  and  each  gland  as  a 
conglomeration  of  follicles,  terminating  in  a  common  excretory 
canal.  This  opinion  was  received  and  admitted  without  being 
contradicted  until  Ruysch,  and  in  his  times  defended  against 
him  by  Boerhaave.  According  to  Ruysch,  on  the  contrary, 
the  parts  which  have  been  called  glandular  grains,  consisted 
solely  of  minute  intertwined  vessels,  in  which  the  arteries 
should  continue  and  terminate  in  excretory  canals. 

In  each  of  these  two  opinions  there  are  some  things  true  that 
we  must  admit,  and  some  parts  inexact,  that  we  mustr  eject. 
It  is  true,  as  stated  by  Malpighi,  that  a  gland  consists,  like  a 
simple  or  compound  follicle,  of  a  canal  closed  at  the  extremi- 
ty; it  is  true  also,  as  it  is  affirmed  by  Ruysch,  that  each  glandu- 
lar grain,  and  that  the  entire  gland  consists  of  a  mixture  and 
intertwining  of  minute  vessels  with  the  origins  of  the  excre- 
tory ducts;  but  it  is  as  incorrect  to  say,  as  he  has  stated,  that 
the  excretory  ducts  are  the  continuation  of  the  arteries,  as  it 
would  be  inexact  to  say  with  Malpighi,  that  the  radicles  of 
the  excretory  ducts  commence  by  enlargements  or  follicles. 
Perhaps  the  hypothesis  of  Malpighi  would  be  more  probable 
if  confined  to  the  granulated  glands,  as  the  salivary,  the  pan- 
creas and  lachrymal  glands,  which,  in  fact,  so  much  resemble 
compound  follicles;  and  that  of  Ruysch  would  more  likely  be 
true  by  applying  it  only  to  the  liver,  the  kidneys  and  testicles, 
the  texture  of  which  is  so  evidently  vascular  and  canaliculated, 
without,  however,  being  able  to  affirm  that  true  hollow  follicles 
exist  in  the  first  mentioned  organs,  and  in  the  others  direct 
continuations  between  the  arteries  and  the  excretory  ducts. 

In  support  of  this  conjecture  might  be  adduced  the  facility 
with  which,  in  the  latter  glands,  injections  pass  from  the  ves- 
42 


320  GENERAL  ANATOMY. 

sels  to  the  excretory  ducts,  and  vice  versa;  and  the  difficulty 
encountered  in  obtaining  the  same  results  in  the  lobulated  and 
granulated  glands. 

However  this  may  be,  the  texture  of  the  glands  seems  very 
positively  to  result  from  the  intimate  association  of  ramified 
excretory  ducts,  closed  at  their  origin,  with  blood-vessels, 
lymphatics  and  nerves,  situated  in  their  intervals,  dividing 
and  terminating  in  their  thickness;  the  whole  being  united  by 
cellular  tissue  and  enveloped  in  membranes. 

§  488.  The  function  of  the  glands  consists  in  a  mode  of  secre- 
tion which  is  called  glandular.  All  secretions  generally  con- 
sist in  the  formation  of  a  particular  humour,  of  which  the 
blood  furnishes  the  materials.  Glandular  secretion  only  dif- 
fers from  $e  others,  (the  follicular  and  perspiratory  secre- 
tions,) by  the  greater  complication  of  its  organs. 

With  a  single  exception,  the  same  blood,  arterial  blood  only, 
is  sent  into  all  the  glands ;  the  number,  the  size,  the  direction, 
the  mode  of  distribution  of  the  vessels,  and  the  degree  of 
tenuity  which  they  reach  by  their  successive  divisions,  can 
only  have  an  influence  on  the  quantity  of  blood  which  arrives 
in  the  gland,  and  on  the  rapidity  of  its  course.  However,  a 
part  of  the  blood  being  brought  back  by  the  veins,  and  another 
liquid  by  the  lymphatics,  the  glands  pour  forth  through  their 
excretory  ducts,  humours  as  different  from  each  other,  as  the 
saliva,  the  tears,  the  bile,  the  urine,  the  sperm  and  the  milk. 

What  are  then  the  nature  and  cause  of  the  conversion  of  the 
blood  into  secreted  humours?  It  has  been  thought  that  the 
change  and  its  cause  were  purely  mechanical,  and  depend  on 
the  size  and  shape  of  the  openings  through  which  the  humours 
issue  from  the  vessels;  it  has  been  supposed  with  more  proba- 
bility, that  it  was  owing  to  a  chemical  change,  that  is  to  say, 
another  elementary  composition;  but  this  change  occurs  only 
in  organized  bodies,  and  in  some  of  their  organs.  This  differ- 
ence is  then  owing  to  modifications  of  their  substance,  in  the 
same  manner  as  we  see  different  vegetables  planted  in  the 
same  soil,  and  surrounded  by  the  same  atmosphere,  produce, 
some  gum,  others  an  acid,  others  resin,  &c.  Glandular  se- 
cretion, like  the  others,  is  then  a  function  of  the  living  and 


OF  THE  GLANDS.  .'321 

organized  substance.  The  vessels  carry  to  it  the  materials 
contained  in  the  blood,  the  production  is  even  probably  dis- 
posed or  prepared  by  the  arrangement  of  the  vessels  and  the 
mode  of  circulation  which  results  from  it;  but  it  is  in  the  tis- 
sue which  forms  the  radicles  of  the  excretory  ducts  that  we 
must  seek  for  its  essential  and  immediate  instrument.  Se- 
cretion generally  and  glandular  secretion  in  particular,  are 
evidently  submitted  to  nervous  influence;  the  effects  of  the 
passions  on  secretions  in  general,  those  of  diseases,  of  hyste- 
ria, of  hypochondria,  &c.  are  sufficiently  known.  Brodie's 
experiments  have  confirmed  that  which  direct  observation  had 
taught. 

The  application  of  a  ligature  to  the  veins  of  a  gland  greatly 
augments  its  secretion. 

§  489.  The  /first  part  which  begins  to  be  formed  in  the 
glands  is  their  excretory  duct.  In  the  embryo,  this  canal  is 
free  and  floating,  as  in  insects.  The  glands  are  afterwards 
lobate,  for  instance  the  kidneys,  as  they  are  in  the  arachnides 
and  crustacea.  They  are  generally  very  voluminous  in  the 
foetus  and  in  the  child.  They  diminish  in  proportion  as  the 
organs  of  the  animal  functions  are  developed.  Some  change 
their  situation  at  the  time  of  birth:  these  are  the  testicles  and 
ovaries.  These  glands  and  the  mammae  are  greatly  developed 
at  the  epoch  of  puberty  and  wither  in  old  age. 

§490.  The  glands  present  many  individual  varieties  and 
vices  of  conformation.  Some  are  sometimes  entirely  wanted: 
those  of  generation  are  mostly  subject  to  this  circumstance. 
One  of  the  double  glands  may  be  wanting  or  be  less  volumin- 
ous than  the  other.  Some  remain  often  lobate,  or  very  vo- 
luminous, as  in  the  foetus.  Others  are  sometimes  united  as 
the  two  kidneys  in  one.  Others  may  keep  their  primitive 
situation,  as  the  testicles  and  ovaries;  these  latter  are  some- 
times, on  the  contrary,  protruded  out  of  the  abdomen.  The 
kidneys  also  may  be  situated  a  great  deal  too  low,  or  in  the 
pelvis. 

§  491.  We  often  observe  the  atrophy  of  the  glands,  either 
in  consequence  of  external  pressure,  or  of  an  accidental  pro- 
duction developed  in  their  thickness:  this  also  occurs  for  want 


322  GENERAL  ANATOMY. 

of  action,  or  even  without  an  appreciable  cause.  Hypertro- 
phia  sometimes  takes  place  as  the  effect  of  the  cessation  of  the 
action  of  other  organs  and  especially  of  a  double  gland.  It  is 
frequently  accompanied  with  some  alteration  of  structure. 

§  492.  The  inflammation  of  the  glands  is  common,  and  often 
occurs  by  extending  all  the  way  in  the  excretory  canal,  from 
its  orifice  to  its  radicles  in  the  gland.  Inflammation  in  them 
is  often  suppurative  and  sometimes  plastic;  from  which  results 
the  obliteration  of  the  ducts  and  the  induration  of  the  tissue. 

§  493.  Accidental  productions,  either  healthy  or  morbid,  are 
very  common  in  the  glands.  The  ovaries  are  most  subject  to 
them,  but  especially  to  analogous  productions;  the  testicles, 
the  liver  and  mammae,  are  very  subject  to  morbid  ones;  the 
lachrymal  and  salivary  glands,  and  pancreas,  are,  on  the  con- 
trary, very  little  liable,  either  to  the  one  or  to  the  other  acci- 
dental productions. 

§  494.  Glandular  tissue  is  not  produced  accidentally.  When 
it  is  wounded,  the  radicles  or  trunk  of  the  excretory  duct  be- 
ing divided,  the  secreted  matter  is  poured  into  the  wound, 
which  has  a  great  tendency  to  become  fistulous  and  to  remain 
so. 

§  495.  Here  ends  the  description  of  all  the  systems  or  kinds 
of  organs  which  belong  especially  to  the  vegetative  functions; 
those  which  remain  to  be  described  belong  more  particularly 
to  the  animal  functions.  This  distinction  would  be  obvious  did 
not  one  of  the  tegumentary  membranes,  the  mucous  membrane, 
belong  principally  to  the  functions  of  nutrition  and  generation ; 
while  the  other,  the  skin,  is  chiefly  subservient  to  the  sensa- 
tions: it  is  the  tegumentary  system  which  unites  the  two  classes 
of  functions  and  organs. 


OF  THE  LIGAMENTOUS  TISSUE.  323 


CHAPTER  VI. 


OF  THE  LIGAMENTOUS  TISSUE. 

§  496.  The  ligamentous  or  desmous  tissue,  textus  desmosus, 
is  white,  flexible,  very  tenacious,  and  forms  very  solid  ties 
and  envelopes. 

It  has  been  designated  by  the  names  of  fibrous,  albugineous, 
tendinous,  aponeurotic,  &c.  tissue.  These  two  latter  names, 
as  well  as  that  of  ligamentous,  have  the  inconvenience  of  de- 
signating one  particular  kind  of  this  tissue,  and  the  first,  a  qua- 
lity common  to  many  others;  for  which  reason  the  name 
desmous  appears  to  me  preferable,  because,  although  it  signi- 
fies ligamentous,  it  has  not  been  applied  to  the  ligaments  in 
particular. 

§  497.  The  most  ancient  anatomists,  Hippocrates  and  Aris- 
totle, confounded  under  the  name  of  nerves  all  the  white  parts; 
hence  the  names  of  aponeurosis,  syneurosis,  ineuration,  semi- 
nervous  muscles,  &c.  The  school  of  Alexandria,  and  especial- 
ly Galen,  have  positively  distinguished  the  ligaments,  tendons 
and  nerves. 

Galen  and  Vesalius  had  already  noticed  the  analogy  which 
exists  between  the  ligaments  and  some  membranes;  Ad.  Mur- 
ray had  already  indicated  the  very  great  resemblance  which 
exists  between  the  tendons,  ligaments  and  aponeuroses.  Isen- 
fiamm*  has  given  some  remarks  on  this  tissue;  but  it  is  Bichat, 
who  first  considered  as  a  whole  every  part  of  this  system  un- 
der the  name  of  fibrous  tissue.  He  comprehended  in  it  the 
elastic  tissue,  which  I  have  separated  from  it,  [361.]  and  ex- 

*  Bemerkungen  iiber  die  fachsen,  in  Beitragefur  die  zcrgliederungskunst. 
Band.  i.  Leipzig,  1800. 


324  GENERAL  ANATOMY. 

eluded  another  kind  that  I  have  united  with  it;  it  is  the  one 
which  he  calls  libro-cartilaginous  of  the  articulations,  and  the 
tendinous  sheaths  in  which  the  tendons  slide. 


SECTION  I. 

OF  THE  LIGAMENTOUS  TISSUE  GENERALLY. 

§  498.  The  ligamentous  organs  do  not  form  a  continuous 
connected  whole;  a  centre  and  a  point  of  reunion  has  been 
sought  for  all  the  parts  of  this  system. 

A  very  ancient  opinion,  anterior  to  Galen,  but  announced 
in  one  of  his  treatises,  ascribed  to  the  pericranium  the  origin 
of  all  the  nervous  membranes.  It  has  been  supposed  that  the 
Arabs,  in  translating  into  their  language  the  name  meninges 
by  a  word  having  the  same  signification,  and  also  that  of  ma- 
ter, considered  the  membranes  of  the  brain  as  generating  the 
other  membranes;  this  is,  however,  an  error  advocated  by 
Sylvius,  who  has  represented  the  meninges  as  fecund  am\  mo- 
thers membranes.  Since  Bonn,  and  recently  Clarus,  have  at- 
tributed, in  a  manner,  the  same  power  to  the  enveloping  apo- 
neuroses.  Bichat  has  indicated  the  periosteum  as  the  central 
part  of  the  fibrous  system.  But  this  system,  formed  of  inde- 
pendent parts,  has  not,  properly  speaking,  any  centre;  some 
of  its  parts  are  even  entirely  isolated  from  the  others.  It  is, 
however,  a  very  generally  disseminated  tissue,  having  great 
affinity  to  the  cellular  tissue,  and  in  various  places  continuous 
with  it 

§  499.  The  ligamentous  tissue  presents  itself  under  two 
principal  forms,  that  of  the  band  or  cord,  as  the  ligaments  and 
tendons;  and  that  of  membrane  or  envelope,  as  the  periosteum, 
the  dura  mater,  the  sclerotica,  &c.  These  two  forms,  funi- 
cular and  membranous,  are  confounded  in  certain  parts,  which 
are  elongated  and  rounded  at  one  extremity,  expanded  and 
flattened  at  the  other,  such  are  certain  tendons;  besides,  the 
membranous  form,  although  generally  destined  to  make  en- 


OF  THE   LTGAMENTOUS  TISSUE  GENERALLY.  325 

velopes,  sometimes  also  constitute  ties:  such  are  the  capsular 
ligaments,  the  aponeuroses  of  insertion,  &c.  The  ligamentous 
tissue  has  also  been  divided,  according  to  its  connexions,  into 
the  parts  subservient  to  the  bones,  to  the  muscles  and  other 
organs;  and  according  to  its  uses, into  parts  serving  for  attach- 
ments or  envelopes,  or  for  both  uses. 

§  500.  The  colour  of  the  ligamentous  tissue  is  white;  its  as- 
pect is  generally  shiny  or  silky. 

§  501.  Its  texture  is  essentially  fibrous,  the  fibres  composing 
it  are  very  minute  filaments,  which  are  parallel  or  interlaced. 
In  long  and  slender  tendons,  the  fibres  are  as  it  were  braided; 
in  the  aponeuroses,  they  are  commonly  disposed  in  several 
layers  crossing  each  other,  and  sometimes  as  it  were  inter- 
woven. In  some  parts  of  this  tissue,  the  fibres  are  so  closely 
united,  that  the  whole  appears  homogeneous  and  not  fibrous; 
such  are  the  cartilaginiform  ligaments;  but  in  every  other  part 
we  may,  in  dropsical  subjects,  or  in  parts  which  may  have 
been  macerated,  separate  the  fibrous  bundles  from  each  other, 
and  even  the  fibres  themselves  in  fine  filaments  resembling  the 
threads  of  the  silkworm.  It  is  not  known  if  this,  be  the  last 
point  of  division,  but  this  is  probable.  These  filaments  are 
white,  tenacious,  slightly  elastic,  flexible,  and  probably  full  or 
solid.  Fontana  and  Chaussier  consider  this  fibre  as  being 
primitive  and  particular;  Isenflamm  considers  it  as  being  form- 
ed of  cellular  filaments  impregnated  with  gluten  and  albumen; 
Mascagni  remarks  that  microscopical  inspection  seems  to  de- 
monstrate that  these  primitive  filaments  result  from  a  collec- 
tion of  absorbent  vessels  surrounded  by  a  membrane  formed 
of  these  same  vessels,  and  of  another  resulting  from  very  mi- 
nute blood-vessels  making  a  very  fine  net-work.  We  see  that 
this  is  still  the  same  idea  already  mentioned  above  [394.] 
These  filaments  appear  to  be  very  condensed  cellular  tissue; 
maceration  softens  and  changes  them  into  a  mucous  or  cellu- 
lar substance. 

The  various  ligamentous  organs  are  enveloped  in  sheaths 
formed  of  cellular  tissue;  moreover,  those  which  have  distinct 
bundles  contain  also  some  of  this  tissue  in  their  interstitial 
spaces;  finally,  the  fibres  themselves  -are  surrounded  and  bound 


326  GENERAL  ANATOMY. 

together  by  this  tissue,  that  infiltration  and  maceration  render 
very  apparent.  We  find  adipose  tissue  also  in  the  thickness 
of  the  ligamentous  organs.  The  ligamentous  tissue  is  gene- 
rally but  little  vascular;  nevertheless,  we  find  at  its  surface, 
and  we  may  follow  into  its  substance  some  small  blood-vessels. 
In  order  to  make  them  visible,  we  must,  after  having  injected 
them  with  a  red  injection,  dry  the  part,  then  dip  it  in  oil 
of  turpentine  to  render  it  transparent.  Some  portions  of  the 
ligamentous  tissue  are  very  vascular;  such  especially  are  the 
periosteum  and  dura  mater.  Lymphatic  vessels  are  perceived 
in  the  largest  organs  of  this  system.  It  is  doubtful  if  there  be 
any  nerves. 

§502.  The  ligamentous  tissue  naturally  contains  a  great 
proportion  of  water.  Dessiccation  renders  it  hard,  trans- 
parent, elastic  and  brittle;  gives  it  a  reddish  or  yellowish  co- 
lour, and  renders  its  fibres  only  slightly  distinct.  It  long  re- 
sists maceration,  which  softens  and  renders  it  floculent  at  its 
surface,  separates  its  fibres,  by  rendering  apparent  the  cellular 
tissue  in  its  thickness,  and  finally  converts  the  fibres  them- 
selves into  mucous  substance.  Fire  violently  crisps  it,  and 
leaves  behind  a  large  quantity  of  charcoal.  Decoction  crisps  it 
very  much  at  first,  renders  it  yellow,  hard,  elastic,  and  finally 
reduces  it  into  gelatin.  Cold  and  warm  mineral  acids  dissolve  it: 
nitric  acid  commences  with  crisping  it.  Cold  acitic  acid 
swells  and  reduces  it  into  a  gelatinous  mass;  when  warm  it 
melts  it  entirely.  Alkalies  swell  and  soften  it;  in  this  state  its 
fibres  separate  easily,  and  present  the  colours  of  the  rainbow. 
§  503.  The  elasticity  of  the  ligamentous  tissue  when  fresh  is 
very  moderate,  but  it  is  strongly  marked  when  dry.  Its  ex- 
tensibility is  almost  null,  when  the  effort  is  sudden;  hence  the 
strangulation  produced  by  ligamentous  parts,  and  the  rupture 
of  this  tissue  by  violent  distention.  But  when,  on  the  con- 
trary, the  causes  of  distention  act  slowly  and  gradually,  the 
ligamentous  tissue  yield  by  becoming  thinner  and  its  fibres 
looser,  and  if  the  slow  distention  be  carried  too  far,  they  even 
separate.  We  must  not  confound  with  this  phenomenon  the 
augmentation  of  the  volume  of  the  fibrous  tissue  by  excess  of 
nutrition.  The  retractility  of  this  tissue  is  proportionate  to 


OP  THE  LIGAMENTOTJS  TISSUE  GENERALLY.  327 

the  extensibility;  it  occurs  quickly  if  the  distention  has  been 
sudden;  without,  however,  producing  laceration,  and  slowly  if 
it  has  been  gradual  and  slow.  The  tenacity  or  power  of  re- 
sistance of  this  tissue  against  laceration  is  very  great;  it  per- 
sists in  all  its  energy  even  after  death;  the  vital  irritability 
and  contractility  is  null  in  this  tissue;  therefore  we  must  not 
admit,  with  Baglivi,  movements  of  contraction,  nor  those  of 
oscillation  with  La  Gaze.  The  sensibility  of  this  tissue  is  ex- 
tremely obscure  and  doubtful.  Those  writers  who  admit  it, 
confess  that  it  is  only  developed  by  certain  mechanical  agents, 
particularly  for  the  various  parts  of  this  system.  Thus  the 
dura  mater  should  be  sensible  to  the  impression  produced  by 
some  excitants,  which  have  no  effect  on  other  ligamentous 
parts;  ligaments  should  be  sensible  to  distention,  and  to  violent 
pulling  which  precedes  their  laceration,  while  the  same  thing 
does  not  occur  in  the  tendons.  Many  doubts  still  exist  on  this 
subject.  It  is  wrong,  however,  to  conclude  from  the  experi- 
ments favourable  to  the  opinion  of  the  insensibility  of  the  liga- 
mentous parts,  that  they  experience  no  impression  from  irri- 
tating causes;  on  the  contrary,  these  causes  induce  inflamma- 
tion, morbid  sensibility,  and  diverse  alterations  in  them.  The 
power  of  formation  of  the  ligamentous  tissue  is  very  active. 

§  504.  The  function  of  this  tissue,  entirely  mechanical,  is  to 
form  ties,  cords,  very  solid  envelopes,  which  serve  to  attach 
the  bones  with  each  other,  and  the  muscles  to  the  bones;  to 
inclose  and  contain  certain  parts;  to  transmit  efforts,  &c. 

§  505.  The  ligamentous  tissue  is  at  first,  in  the  embryo,  soft 
and  mucous  like  all  the  other  parts;  it  continues  to  have,  dur- 
ing gestation  and  infancy,  a  great  deal  of  softness  and  flexi- 
bility; it  is  then  but  slightly  dense,  more  vascular,  of  a  bluish 
white,  with  pearly  or  silvery  lustre,  and  easily  soluble  in  boil- 
ing water.  Some  parts,  like  the  dura  mater,  the  sclerotica  and 
periosteum,  are  thicker  than  in  the  adult;  the  tendons  and  apo- 
neuroses,  on  the  contrary,  are  more  slender  and  thinner.  In 
old  age,  on  the  contrary,  it  becomes  yellow,  has  less  lustre,  is 
firmer,  more  coriacious,  dryer,  less  vascular,  and  less  soluble 
in  boiling  water  than  it  is  in  the  adult. 

Notwithstanding  the  firmness  of  the  ligamentous  tissue  in 
43 


328  CSENERAL  ANATOMY. 

old  persons,  it  has  not  a  very  great  predisposition  to  ossifica- 
tion. The  tendons  are  seldom  ossified  except  where  they  rub, 
and  where  they  have  a  fibro-cartilaginous  texture,  and  at  their 
extremity  where  inserted  into  the  bones.  The  rare  occurrence 
of  senile  ossification  of  the  tendons  is  so  much  the  more  re- 
markable, as  in  various  animals,  as  certain  birds,  or  as  the  in- 
sects and  the  Crustacea?,  ossification  or  an  analogous  indura- 
tion always  occurs  in  the  regular  development  of  these  parts. 

§  506.  The  different  parts  of  the  fibrous  system,  although 
sufficiently  analogous  to  form  one  kind  of  organs,  they  are  not, 
however,  identical;  the  texture  of  the  tendons  is  less  close  than 
that  of  the  ligaments,  that  of  the  cartilaginiform  ligaments  is 
so  compact,  that  it  appears  almost  homogeneous.  The  chemi- 
cal composition  of  all  these  parts  is  nearly  the  same;  the  ten- 
dons yield,  however,  much  more  easily  to  the  dissolving  action 
of  boiling  water,  than  the  other  ligamentous  parts. 

§  507.  The  ligamentous  tissue,  when  divided,  torn  or  lace- 
rated, reunites:  this  we  see  occurring  in  the  ligaments  after 
luxations.  The  tendo  achilli,  or  some  other  large  tendon  be- 
ing lacerated,  if  the  ends  are  kept  motionless  and  in  contact, 
there  occurs  at  first  an  agglutination  between  them,  then  an 
organic  reunion  which,  more  extensible  at  first  than  the  ten- 
don, acquires  in  time  its  force  of  cohesion,  or  its  tenacity  and 
its  almost  inextensible  character.  There  takes  place  between 
the  extremities  of  divided  muscles,  and  sometimes  after  the 
fractures  of  bones,  fibrous  reunions. 

§  508.  The  accidental  productions  of  the  ligamentous  tissue 
is  pretty  frequent,  and  presents  itself  under  several  forms.  We 
find  membranes  of  this  kind  around  certain  cysts jivhich  are, 
however,  seldom  altogether  enveloped  by  it.  Some  solid  tu- 
mours have  also  envelopes  of  the  same  kind.  Preternatural 
joints  have  also  fibrous  capsules  more  or  less  distinct.  We 
sometimes  find  fibrous  bands  in  the  serous  membranes,  and 
especially  in  the  pleura. 

The  isolated  fibrous  or  ligamentous  bodies  have  been  very 
anciently  observed,  but  confounded  with  schirrhus ;  M.  Cham- 
bon  has  described  them  under  the  name  of  scleromes.  Walter 
and  Baillie  were  acquainted  with  them.  Bichat,  and  after  him 


OF  THE  LIGAMENTOUS  TISSUE  GENERALLY. 

M.  Roux,  have  described  them;  but  it  is  to  Bayle  and  to  Laen- 
nec  that  we  owe  our  complete  knowledge  of  them.  They 
have  a  globular  form,  their  surface  is  unequal  and  as  it  were 
lobated;  the  largest  anfractuosities  contain  vessels  and  infil- 
trated cellular  tissue.  When  split  they  are  seen  to  be  formed 
of  lobules  and  convoluted  bands,  connected  by  cellular  tissue, 
and  of  fibrous  prolongations.  They  have  few  vessels  inter- 
nally. They  are  at  first  small  and  soft  like  the  fibrine  of  the 
blood ;  they  progressively  increase  in  size  and  change  their  tex- 
ture; they  seldom  become  cartilaginous,  but  frequently  osseous; 
an  ossification  of  a  strong  hardness  is  developed  in  them  in  an 
irregular  manner,  and  resembles  in  their  thickness  to  a  mulber- 
ry calculus.  They  are  often  formed  in  the  texture  and  near  the 
surface  of  the  uterus;  sometimes  in  the  ovary,  in  the  acciden- 
tal cellular  tissue  of  the  serous  membranes,  and  are  then  formed 
of  layers  like  a  bulbous  root,  in  the  cellular  tissue;  and  it  has 
been  said  in  the  bones  also;  they  have  been  seen  in  the  fingers 
and  eye-lids,  under  the  mucous  membrane  of  the  nose;  the 
fungi  of  the  dura  mater  are  sometimes  bodies  of  this  kind; 
once  they  have  even  been  seen  in  the  brain. 

Irregular  fibrous  productions  are  found  in  the  cicatrices  of 
the  liver,  bones  and  skin;  in  the  scrotum  and  elsewhere  around 
fistules. 

§  509.  There  is  a  production  which  comes  very  near  the 
ligamentous  tissue:  it  is  that  of  a  white  compact  tissue,  not 
fibrous,  nor  laminar,  nor  cellular,  semi-transparent,  not  chato- 
yant, soft  and  tenacious.  Some  organs  in  a  state  of  atrophy, 
appear  to  be  transformed  into  this  tissue;  the  cicatrices  of  the 
skin,  that  of  the  cellular  tissue  after  the  cure  of  chronic-phleg- 
mous,  and  after  that  of  old  fistulse,  and  some  white  granulations 
of  the  serous  membranes,  resembling  the  glands  of  pachioni, 
are  of  this  kind. 

There  should  also  be  referred  to  it,  the  sclerosis  which  is 
observed  in  the  cellular  tissue  and  the  skin  in  elephantiasis 
of  the  limbs,  scrotum,  and  vulva,  and  which  has  also  been 
seen  in  the  subperitoneal  cellular  tissue,  in  a  case  of  cancer. 

It  is  to  this  production  that  we,  must  also  refer  the  greater 
number  of  the  polypi  of  the  uterus  and  especially  of  the  va- 


330  GENERAL  ANATOMY. 

gina,  and  some  tumours  projecting  under  the  skin;  polypi  and 
tumours,  whose  white,  compact,  soft  and  tenacious  tissue, 
differs  from  the  fibrous  tissue,  but  bears  more  resemblance  to 
it  than  to  any  other. 

These  varieties  of  accidental  white  tissue  have  somewhat  a 
slight  resemblance  to  morbid  productions  by  their  tendency 
to  spread  and  to  reappear. 

§  510.  The  inflammation  of  the  ligamentous  tissue  is  little 
known,  but  is  not  of  very  rare  occurrence. 

It  most  frequently  terminates  by  resolution,  often  also  by 
the  production  of  a  plastic  or  organizable  matter,  which  is 
sometimes  absorbed,  and  at  others  gives  rise  to  accidental  ossi- 
fication. Chronic  inflammation  softens  this  tissue,  causes  it  to 
lose  its  tenacity,  and  sometimes  also  gives  rise  to  its  ossification. 

Some  fungus  of  the  dura  mater  contain  polypi  of  the  nasal 
fossae,  and  posterior  parts  of  the  nostrils,  certain  epulies,  some 
tumours  of  the  periosteum,  are  morbid  productions  or  cancer- 
ous degenerations  of  the  ligamentous  tissue. 


SECTION  II. 

OF  THE  LIGAMENTOUS  ORGANS  IN  PARTICULAR. 

§511.  Overlooking  for  the  present  the  h'bro-cartilaginous 
tissue,  the  fibrous  organs  may  be  divided  into  those  which 
bind  the  bones  with  each  other,  those  which  attach  the  mus- 
cles to  the  bones,  and  those  which  form  envelopes. 

ARTICLE  I. 
OF  THE  LIGAMENTS. 

§  512.  The  ligaments,*  ligamenta  nervi  colligantes, 
cvfisor/toi,  are  the  fibres  which  connect  the  bones  and  cartilages 
with  each  other. 

*  Jos.  Wcitbrecht,  syndesmobgia  site  hialoria  ligament,  corp.  hum,  &c. 
cum  Jiguris,  4to.  Petropol.  1742. 


OP  THE  LIGAMENTS.  331 

The  same  name  has  improperly  been  given  to  many  other 
parts  and  especially  to  bridles  formed  by  folds  of  the  serous 
and  mucous  membranes,  to  serous  and  adipose  prolonga- 
tions, &c. 

The  true  ligaments  are  attached  by  their  two  extremities  to 
the  bones  and  periosteum,  and  so  firmly,  that  in  the  adult,  it 
requires  an  advanced  stage  of  putrefaction  to  separate  them; 
but  in  children  they  separate  from  the  bones  with  the  perios- 
teum by  a  moderate  maceration. 

The  fibrous  tissue  which  enters  into  their  composition  is 
very  dense,  and  arranged  in  more  or  less  distinct  bundles,  very 
closely  connected;  some  go  even  so  far  as  to  have  the  appa- 
rent homogeneous  structure  of  the  cartilages. 

By  decoction,  they  are  resolved,  though  with  difficulty,  into 
gelatine  and  albumen. 

§513.  The  ligaments  are  often  affected  with  inflammation, 
either  through  mechanical  causes,  as  those  of  sprains  and  frac- 
tures in  the  articular  parts  of  the  bones,  or  through  the  in- 
flamed neighbouring  synovial  membranes,  or  through  the  spe- 
cific causes  of  articular  rheumatism  and  gout.  Inflammation 
gives  rise  to  two  different  effects  in  the  ligaments:  namely,  an 
extreme  softening  and  a  loss  of  their  power  of  resistance,  or 
accidental  ossification.  This  last  change  is  the  most  frequent; 
the  other  is  especially  observed  in  the  scrofulous  diseases  of 
the  articulations. 

According  to  their  connexions  and  uses,  the  ligaments  are 
distinguished  in  articular,  non-articular,  and  mixed.  The 
first  are  those  which  are  attached  by  their  extremities  to  dif- 
ferent bones  that  they  connect,  these  are  the  most  important; 
the  second  kind  are  those,  which  attached  to  different  parts  of 
the  same  bone,  serve  to  close  notches,  as  at  the  orbital  arch 
and  at  the  superior  margin  of  the  scapulae,  or  to  close  an  open- 
ing and  give  attachment  to  muscles,  like  the  obturator  liga- 
ment of  the  foramen  ovale;  the  last  are  those  which,  like  the 
sacro-ischiatic  and  interosseous  ligaments  of  the  arm  and  leg, 
are  fixed  to  different  bones,  but  serve  especially  for  the  inser- 
tion of  muscles. 


332  GENERAL  ANATOMY. 

The  articular  ligaments  are  distinguished  into  capsular  and 
funicular. 

The  capsular  ligaments  or  fibrous  capsules  consist  of  cylin- 
droid  ligamentous  sheaths  which  surround  the  articulation, 
which  are  fastened  by  their  two  extremities  to  the  two  articu- 
lated bones,  and  are  lined  internally  by  the  synovial  mem- 
brane. These  capsules,  while  they  firmly  connect  the  bones, 
allow  of  motions  in  all  directions.  They  are  almost  peculiar 
to  the  scapulo-humeral  and  coxo-femoral  articulations;  how- 
ever, rudiments  of  them  are  to  be  found  in  some  others,  in 
which  irregular  bundles  strengthen  the  synovial  membrane 
in  several  points  of  its  contour. 

The  cords  or  ligamentous  bundles  of  the  articulations  are 
rounded  strings  or  flattened  bands,  mostly  situated  outside  of 
the  joints,  and  few  of  them  only  in  the  articular  cavities,  Both 
permit  movements  in  some  directions,  but  prevent  or  limit 
them  in  others. 

The  external  ligaments  are  mostly  placed  at  the  two  sides 
of  the  articulation,  and  for  this  reason  are  called  lateral  liga- 
ments; many  moveable  articulations  are  provided  with  them; 
others  are  anterior  and  posterior;  some,  in  consequence  of 
their  direction,  are  called  crucial  ligaments.  All  these  liga- 
ments, which  are  attached  by  their  two  ends  to  the  bones, 
correspond  by  one  of  their  faces  to  the  synovial  membrane, 
and  by  the  other  to  the  surrounding  common  cellular  tissue, 
muscles  and  tendons. 

The  internal  ligaments  are  surrounded  by  a  sheath  furnished 
by  the  synovial  membrane,  which  is  reflected  at  their  two  ex- 
tremities [212]. 


ARTICLE  II. 
OP  THE  TENDONS. 

§515.  The  ligaments  of  the  muscles  or  the  tendons,*  ten- 
dines,  tivovt^ydire  ligamentous  parts  to  which  are  attached  the 
extremities  of  the  muscular  fibres. 

*  Albinus,  annoi.  acad.,  lib.  vi.,  cap.  7,  et  tab.  5. 


OF  THE  TENDONS. 

Among  the  tendons,  some  are  funicular,  and  have  the  form 
of  an  elongated,  rounded  or  flattened,  but  narrow  cord,  these 
are  the  tendons  properly  so  called;  the  others  are  expanded 
and  membraniform,  those  are  the  aponeurotic  tendons  or  the 
aponeufoses  of  attachment. 

Both  are  chiefly  placed  at  the  extremities  of  the  muscles, 
and  serve  to  insert  them;  the  others,  placed  lengthwise  and 
interrupting  the  fleshy  fibres,  are  tendons  and  aponeuroses  of 
intersection  or  enervations. 

Among  the  tendons  of  insertion,  there  are  even  some,  which 
consisting  in  a  multitude  of  small  isolated  fibrous  bundles, 
have  neither  the  form  of  a  cord  nor  of  a  membrane. 

There  are  others  which  form  arches  attached  by  their  two 
extremities,  and  under  which  vessels  pass;  such  is  the  one 
under  which  pass  the  femoral  vessels  to  become  popliteal,  &c. 

Among  the  tendons  there  are  some  which  have  the  form  of 
a  cord  in  the  greater  part  of  their  length,  and  which,  at  one  of 
their  extremities,  or  both,  expand  into  membranes. 

There  are  others  which  are  simple  at  one  extremity,  and 
divide  at  the  other  into  several  cords  or  into  laminae  of  greater 
or  less  breadth. 

The  connexion  of  the  tendons  with  the  muscular  fibres  is 
very  firm;  it  has  even  been  asserted  that  there  are  a  real  con- 
tinuity and  identity  between  these  parts.  But,  besides  the 
difference  of  density  and  colour,  besides  the  remarkable  dif- 
ference which  is  perceived  with  the  microscope  between  the 
two  tissues,  we  remark  aponeurotic  tendons  whose  fibres  have 
a  different  direction  from  those  of  the  muscles;  the  tendons 
are  moreover  much  less  vascular  than  the  muscles;  they  are 
proportionally  longer  in  children ;  they  separate  from  the 
muscles  by  decoction;  they  are  resolved  into  cellular  tissue 
by  maceration;  they  are  not  irritable  like  the  muscular  fibres, 
&c.;  they  are  not  the  continuation  of  the  latter,  but  simply 
that  of  the  cellular  tissue  of  the  muscles. 

By  the  other  extremity  the  tendons  are  attached  to  the 
bones,  and  generally  near  the  articulations.  Some  aponeu- 
rotic tendons,  instead  of  directly  attaching  themselves  to  the 


334  GENERAL  ANATOMY. 

bones,  expand  and  are  confounded  with  the  envelopes  of  the 
muscles. 

The  tendons  are  surrounded  with  common  and  lax  cellular 
tissue,  or  with  mucilaginous  bursae,  according  to  the  extent  of 
the  sliding  they  experience. 

Some  are  kept  in  their  respective  places  by  rings  or  sheaths. 

The  colour  of  the  tendons  is  white,  shining,  bordering  on  a 
green,  silky  or  velvety. 

The  fibrous  tissue  which  composes  them  contains  in  its  in- 
terstices, in  the  largest  at  least,  some  cellular  tissue,  and  small 
sanguineous  vessels. 

Some  tendons  have  a  fibro-cartilaginous  texture;  they  are 
those  which  rub  against  the  bones.  They  even,  in  time,  be- 
come bony  at  these  points. 

Their  essential  properties  are  inextensibility  and  force  of 
cohesion,  which  renders  them  well  calculated  to  transmit  to 
the  bones  the  action  of  the  muscles,  the  only  function  they 
have  to  perform. 

They  are  seldom  altered;  puncture  induces  in  them  an  in- 
dolent swelling  which  is  slowly  resolved. 


ARTICLE  III. 
OP  THE  LIGAMENTOUS  ENVELOPES. 

§  517.  The  ligamentous  membranes  furnish  to  certain  parts, 
envelopes  analogous  to  those  that  the  cellular  tissue  forms 
about  certain  other  organs.  These  membranes  are  the  folio  wing: 

A.    OP  THE  ENVELOPES  OP  THE  MUSCLES. 

§  518.  The  envelopes  of  the  muscles,  or  the  enveloping 
aponeuroses  also  furnish,  in  some  places,  insertions  to  the  mus- 
cular fibres;  they  are  of  two  kinds,  some  surround  the  muscles 
of  the  members,  others  invest  those  of  the  parietes  of  the  trunk. 

§519.  The  enveloping  aponeuroses  of  the  limbs,  fasciae 
muscularesf  are  ligamentous  membranes  which  surround  the 

*  Ad.  Murray,  de  Fastix  hta.  Upsal,  1774. 


OP  THE  ENVELOPES  OP  THE  MUSCLES.  335 

muscles  of  the  limbs  and  binds  them  down  to  the  bones. 
These  membranes  have  the  form  of  sheaths;  their  external 
surface  corresponds  to  the  cellular  and  adipose  tissues,  as  well 
as  to  the  subcutaneous  vessels  and  nerves.  Their  inner  sur- 
face corresponds  to  the  muscles,  furnishes  attachments  to  some 
of  them,  sends  laminae  between  the  greater  number  of  them, 
partitions,  prolongations  which  separate  them  from  each  other, 
which  furnish  attachments  to  them,  and  terminate  by  inserting 
themselves  on  the  ridges  and  lines  of  the  bones.  Their  ex- 
tremities are  attached  to  the  bones,  receiving  insertions  or  ex- 
pansions of  the  tendons,  losing  themselves  insensibly  in  the 
cellular  tissue,  and  in  other  places  forming  annular  ligaments 
to  the  tendons.  They  consist  of  one  or  more  layers  of  liga- 
mentous  tissue  of  variable  thickness,  and  are  proportionate  in 
their  thickness  to  the  number  and  strength  of  the  muscles  that 
they  embrace;  they  present  openings  for  the  passage  of  vessels 
from  the  deep  to  the  superficial  plane  and  vice  versa.  They 
are  provided  with  tensor  muscles,  either  proper,  or  simply  by 
the  expansion  of  their  tendons.  Their  uses  are  to  keep  the 
muscles  in  their  proper  places,  and  to  furnish  them  with  points 
of  attachment.  They  exercise  by  their  resistance  a  slight 
pressure  on  the  deep  vessels,  and  thus  favour  the  venous  and 
lymphatic  circulation.  Their  knowledge  is  of  great  im- 
portance in  a  pathological  point  of  view,  on  account  of  the 
strangulations  which  they  may  induce;  nor  is  its  knowledge 
less  so  in  surgery,  in  consequence  of  their  relations  with  the 
muscles  and  vessels. 

The  thigh,  the  leg,  the  foot,  the  hand,  the  fore-arm  and  arm, 
are  provided  with  aponeuroses  of  this  kind. 

§  520.  The  aponeuroses  of  the  parietes  of  the  cavities  of  the 
trunk,  or  the  partial  aponeuroses,  invest,  cover,  and  even  en- 
velop, at  least  in  part,  certain  muscles:  such  are  the  compound 
aponeurotic  sheaths  of  the  recti  and  pyramidales  muscles  of 
the  abdomen;  the  dorsal  aponeurosis  which  covers  the  muscles 
of  the  vertebral  grooves;  the  temporal  aponeurosis;  the  pelvic, 
transversal,  superficial,  jugular  aponeuroses,  &c.  Some,  and 
especially  the  latter,  are  not  very  distinct  from  the  cellular 
tissue,  into  which  they  are  continued. 
44 


336  GENERAL  ANATOMY. 

B.  OF  THE  SHEATHS  OF  THE  TENDONS. 

§  521.  The  sheaths  of  the  tendons  are  ligamentous  canals 
which  embrace  and  fix  the  tendons  in  their  place. 

Some  of  them  are  sufficiently  long  to  form  true  canals; 
others,  which  are  much  shorter,  are  called  annular  ligaments. 
Some  of  these  annular  ligaments  are  entirely  circular;  others, 
as  well  as  the  sheaths,  are  completed  by  the  neighbouring 
bones,  whence  result  osteo-ligamentous  sheaths.  They  are, 
together  with  the  tendons  which  they  contain,  invested  by  va- 
giniform  synovial  membranes.  These  sheaths  are  very  solid 
and  strong;  they  contain  each  one  or  more  tendons;  they  are 
especially  more  numerous  at  the  free  extremities  of  the  limbs, 
more  in  the  direction  of  flexure,  and  also  stronger  in  this  di- 
rection than  in  that  of  extension.  They  keep  the  tendons  in 
their  proper  place,  prevent  their  displacement  during  the 
action  of  the  muscles  and  the  motions  of  the  joints;  they  also 
serve,  in  some  places,  as  pulleys  which  change  the  direction 
of  the  tendons  and  modify  that  of  the  motions. 

C.    OF  THE  PERIOSTEUM. 

§  522.  The  envelope  of  the  bones,  or  the  periosteum,  em- 
braces the  bones  in  their  whole  extent,  excepting  the  articular 
surfaces.  The  teeth  alone,  which  however  are  not  bones,  are 
destitute  of  it. 

This  envelope  is  interrupted  at  the  amphiorthrodial  and 
diarthrodial  articulations,  but  is  not  so  at  the  immoveable 
ones. 

Its  external  surface  is  flucculent,  and  nearly  covered  with 
filaments  which  confound  themselves  with  the  surrounding 
cellular  tissue,  and  which,  in  other  places,  are  continuous  with 
the  ligaments  and  tendons. 

The  internal  surface  is  fixed  to  the  bone  by  innumerable 
prolongations  which  accompany  the  vessels  into  its  interior 
and  into  its  substance.  This  surface  is  very  firmly  attached 
to  the  bones  wherever  they  are  thick  and  spongy,  but  less  so 
in  the  other  parts.  Its  adhesion  is  also  less  firm  in  children 
than  in  adults. 


OF  THE  PERIOSTEUM.  337 

The  thickness  of  the  periosteum  is  variable,  and  proportion- 
ate to  the  vascularity  of  the  bones. 

Its  texture  is  fibrous,  and  fibro-cartilaginous  in  the  places 
where  the  tendons  rub.  It  has  very  numerous  blood  vessels,* 
and  in  this  respect  forms  a  remarkable  exception  in  the  liga- 
mentous  tissue.  Lymphatic  vessels  have  also  been  observed 
in  it,  but  no  nerves. 

The  periosteum  is  at  first  thin  and  has  little  vascularity 
before  the  period  of  ossification.  It  becomes  thjjik  and  vascu- 
lar at  this  time.  The  use  of  madder  does  not  colour  it. 

The  functions  of  the  periosteum  are  to  envelop  the  bones, 
support  the  vessels,  unite  the  epiphyses,  in  childhood,  to  the 
body  of  the  bone,  and  to  serve  at  this  period  to  insert  the  liga- 
ments and  tendons. 

The  formation  of  bone  has  been  ascribed  to  it,  but  without 
any  proof;  for  the  ossification  of  the  short  bones  is  observed 
to  begin  at  the  centre  of  the  cartilage,  and  therefore  far  from 
the  periosteum ;  and  also  of  determining  the  form  of  the  bones, 
of  limiting  their  growth  by  retaining  the  osseous  humour,  &c. 
As  to  the  part  it  may  perform  in  the  increase  of  the  bones  in 
thickness,  in  the  repairing  the  fractured  bones  or  affected  with 
necrosis,  will  be  examined  hereafter,  (chap,  viii.) 

The  periosteum,  when  divided,  reunites;  when  it  is  re- 
moved a  superficial  necrosis  is  commonly  produced,  and  it  is 
reproduced  after  exfoliation.  When  it  is  inflamed,  sometimes 
is  terminated  by  resolution,  at  others  by  gangrene ;  sometimes 
it  suppurates,  and  then  separates  more  or  less  quickly  from 
the  bone,  which  becomes  affected  with  necrosis ;  at  other  times, 
the  inflammation  being  plastic,  a  deposition  occurs  in  its  thick- 
ness, producing  a  periostosis,  which  is  sometimes  dispersed 
by  absorption,  and  at  others  ossifies.  The  periosteum  is  fre- 
quently the  seat  of  a  degeneration  or  of  a  cerebriform  cancer- 
ous production,  at  the  centre  of  which  the  bone  itself  is  not 
very  materially  altered. 

§  523.  The  perichondrium,  a  ligamentous  membrane  which 

*  See  Ruyscli,  adv.  anal,  dec  iii.  tab.  H.  fig.  8. — Albums,  Icon,  oss-  foetus, 
Tab.  xvi.  fig.  162. 


33S  GENERAL  ANATOMY. 

envelops  the  cartilages,  differs  only  from  the  periosteum  by 
being  less  vascular.  It  fulfils,  with  respect  to  the  cartilages, 
the  same  functions  as  the  periosteum  with  reference  to  the 
bones,  and  moreover,  it  imparts  to  those  which  are  thin  and 
flexible,  a  power  to  resist  rupture,  and  a  tenacity  which  they 
do  not  of  themselves  possess. 

D.    OF  THE  FIBROUS  ENVELOPES  OF  THE  NERVOUS  SYSTBM. 

§  524.  The  nerves  have  a  peculiar  envelope,  the  neurilema, 
which  is  of  the  same  nature  as  the  ligamentous  tissue.  Around 
the  spinal  marrow,  this  envelope  loses  the  firmness  of  the  liga- 
mentous tissue,  and  around  the  brain,  where  the  pise-mater  is 
its  continuation,  it  becomes  simply  cellular  and  vascular.  The 
neurilema,  much  less  vascular  than  the  pia3-mater,  is  still  a 
very  vascular  part  of  the  ligamentous  system. 

§  525.  The  dura-mater  or  menix,  which  is  vascular  like  the 
periosteum,  differs  from  this  common  membrane  of  the  bones, 
in  being  lined  by  the  arachnoid,  which  converts  it  into  a  fibro- 
serous  membrane,  because  it  forms  a  coat  or  capsule  to  the 
brain  and  spinal  marrow,  in  as  much  as  in  the  cranium,  the 
only  place  where  it  also  serves  as  a  periosteum,  it  contains 
sinuses  or  venous  canals  in  its  thickness,  and  forms  prolonga- 
tions or  portions  between  the  divisions  of  the  brain. 

E.    OF  THE  COMPOUND  FIBROUS  MEMBRANES. 

§526.  The  pericardium  and  perididymes  or  tunica  vagina- 
lis  are,  like  the  dura-mater,  fibro-serous  membranes,  being  the 
result  of  the  intimate  union  of  ligamentous  membrane  with 
the  external  or  parietal  layer  of  a  serous  membrane. 

In  the  nasal  fossae  and  their  sinuses,  in  the  cavity  of  the 
tympanum  and  mastoid  cells,  at  the  roof  of  the  mouth  and  in 
some  other  places  also,  the  periosteum  is  immediately  covered 
by  a  mucous  membrane  which  is  intimately  united  to  it,  which 
constitutes  a  fibro-mucous  membrane. 

These  compound  membranes  resemble,  in  their  texture, 
functions,  and  alterations,  the  two  kinds  of  tissue  of  which 
they  are  formed. 


OF  THE  FIBRO-CARTILAGINOUS  TISSUE.  339 

F.    OF  THE  FIBROUS  CAPSULES  OF  SOME  ORGANS. 

§  527.  Finally,  the  eye  is  contained  in  a  capsular  membrane 
called  sclerotica  and  cornea;  the  testicle  in  one  which  is  named 
albuginea,  both  remarkable  for  their  thickness  and  firmness. 
The  ovaries,  the  kidneys,  liver,  and  some  other  parts,  have  en- 
velopes of  the  same  kind,  but  not  nearly  so  thick  or  solid. 
Most  of  these  capsules,  in  fact  all  of  them  excepting  the  scle- 
rotica, have  fibrous  internal  prolongations  which  extend  into 
the  tissue  of  the  organ.  They  are  perforated  by  some  open- 
ings for  the  passage  of  vessels,  but  have  very  little  vascularity 
themselves.  Their  common  uses  are  to  determine  the  form 
of  the  organs  which  they  envelop,  contain,  support,  and  pro- 
tect their  internal  parts. 


SECTION  III. 

OF  THE  FIBRO-CARTILAGINOUS  TISSUE. 

§  528.  The  fibro-cartilaginous  tissue  is  fibrous  and  tenacious 
like  the  ligamentous  tissue,  of  which  it  really  forms  a  part; 
white,  very  dense  and  elastic,  like  the  cartilaginous  tissue,  it 
seems  intermediate  between  the  ligaments  and  cartilages. 

§  529.  Galen  has  named  certain  ligaments  neurochondroid 
f£vpo^ovSpw6£5  awfcs/toe;  Vesalius  calls  them  cartilaginous  liga- 
ments; Morgagni  considers  them  as  intermediate  between  the 
ligamentsand  cartilages;  Weitbrechtcomprehends  them  among 
the  ligaments;  Haase,  on  the  contrary,  classes  them  in  the 
chondrology,  under  the  names  of  ligamentous  and  mixed  car- 
tilages. Bichat  has  established  a  fibro-cartilaginous  system, 
composed  of  the  cartilaginiform  ligamentcus  tissue  of  which 
we  here  speak,  and  of  a  part  of  the  cartilaginous  tissue,  which 
will  be  described  in  the  next  chapter;  but  this  system  of  or- 
gans does  not  appear  to  me  to  exist  in  nature,  for  which  reason 
I  have  rejected  it.  The  fibro-cartilages,  of  which  we  speak, 


340  GENERAL  ANATOMY. 

seems  to  me  to  be  but  a  variety  of  the  desmous  tissue:  they 
are  cartilaginiform  ligamentous  organs. 

§  530.  The  fibro-cartilages  are  either  temporary  or  perma- 
nent. 

The  temporary  fibro-cartilages  are  those  which  pass  regu- 
larly, constantly,  and  at  determinate  epochs  into  the  osseous 
state:  they  are  the  fibro-cartilages  of  ossification.  They  are 
found  in  the  substance  of  the  tendons  and  ligaments.  They 
are  purely  fibrous  in  the  beginning,  afterwards  become  fibro- 
cartilaginous,  and  finally  osseous.  The  patella  and  sesamoid 
bones  are  developed  in  this  manner.  The  places  where  the 
tendons  rub  against  the  bones,  those,  for  instance,  where  the 
gemini  are  applied  on  the  femur,  and  where  the  peronaeus 
lungus  lateralis  slides  on  the  tarsus,  are  also  constantly  the  seat 
of  fibro-cartilages  of  this  kind.  The  stylo-hyoid  and  thyro- 
hyoid  ligaments  contain  grains  of  the  same  nature  in  their 
substance.  The  sclerotica,  in  certain  animals,  presents  opaque 
spots,  equally  fibro-cartilaginous,  which  afterwards  form  bony 
plates. 

§  531.  The  permanent  fibro-cartilages,  or  at  least  those 
which  remain  during  the  greater  part  of  life,  are  of  several 
species.  1st,  There  are  some  which  are  free  at  their  two  sur- 
faces: these  are  the  inter-articular  ligaments,  menisci;  they  are 
met  with  in  thetemporo-maxillar  and  sterno-clavicular  articu- 
lations, sometimes  in  that  of  the  acromion  with  the  clavicle, 
always  between  the  femur  and  tibia,  and  between  the  ulna  and 
pyramidal  bone.  These  ligaments,  perfectly  isolated  at  their 
two  surfaces,  adhere  by  their  edges  or  by  their  extremities. 
2d,  Others  adhere  by  one  of  their  surfaces;  such  are  those 
which  are  found  wherever  a  tendon  rubs  against  a  bone,  and 
the  presence  of  which  is  owing  to  the  circumstance  that  the 
periosteum  becomes  cartilaginous  in  these  places;  and  those 
the  ligaments  present,  against  which  slides  the  tendons,  as  is 
the  case  for  the  calcaneo-cuboidal  ligament,  against  which  the 
tendon  of  the  tibialis  posticus  rubs.  Such  are  also  the  fibro- 
cartilaginous  roundish  borders  attached  to  the  margin  of  the 
glenoid  and  cotyloid  cavities.  Generally,  wherever  the  fibrous 
tissue  is  exposed  to  continued  frictions,  this  tissue  assumes  a 


OF  THE  FIBRO-CARTILAGINOUS  TISSUE.  341 

cartilaginous  texture  or  appearance,  as  is  observed  at  the  an- 
nular ligament  of  the  wrist,  and  the  transverse  ligament  of  the 
odontoid  process  of  the  second  vertebra;  the  pulley  of  the  ob- 
liquus  major  muscle  also  affords  an  instance  of  the  same  kind. 
3d,  Certain  cartilaginous  ligaments  adhere  by  their  two  sur- 
faces; the  intervals  between  the  bodies  of  the  vertebrae  and  the 
interval  between  the  two  ossa  pubis,  are  filled  up  with  organs 
of  this  kind.  Thus,  according  to  their  form  and  connexions, 
there  may  be  distinguished  three  kinds  of  cartilaginiform  liga- 
ments. 

§  532.  These  organs,  although  always  fibrous  like  the  liga- 
ments, and  very  dense  like  the  cartilages,  present  a  great  num- 
ber of  varieties,  with  reference  to  the  consistence  and  homo- 
geneousness  of  their  tissue.  The  minuei,  or  inter-articular 
ligaments,  for  instance,  present  very  distinct  fibres  at  their 
circumference,  and  towards  their  centre,  which  is  thin,  an  ap- 
pearance more  and  more  compact  and  homogeneous,  without, 
however,  meriting,  even  in  that  place,  the  title  of  true  carti- 
lages. The  cartilaginous  periosteum  has  more  resemblance  to 
these  latter.  In  the  amphiarthrodial  ligaments,  a  very  appa- 
rent fibrous  tissue  exists  at  the  exterior.  In  proportion  as  it 
approaches  the  centre,  it  becomes  converted  into  a  kind  of 
pulp  or  white  pap  which  resembles  cartilage,  less  in  its  con- 
sistence, however,  than  from  the  disappearance  of  the  fibres 
and  its  apparent  horaogeneousness. 

§  533.  There  enter  into  the  composition  of  the  fibro-carti- 
lages  the  same  parts  as  into  that  of  the  ligamentous  tissue:  few 
vessels  occur  in  them.  Their  chemical  composition  has  been 
but  little  studied.  They  become  yellow  and  transparent  like 
the  ligaments,  by  desiccation.  Decoction  acts  on  them  in  the 
same  manner  as  on  these  latter;  they  are  entirely  melted  by  it 
into  a  jelly,  so  that  they  do  not,  in  this  respect,  participate  of 
the  nature  of  the  cartilaginous  tissue. 

§  534.  Their  physical  properties  are  similar  to  those  of  the 
ligaments  and  cartilages.  Their  tenacity  or  force  of  cohesion, 
which  is  very  great,  and  even  exceeds  that  of  the  bones,  ap- 
proaches them  to  the  ligamentous  tissue.  On  the  other  hand, 
they  are  very  elastic,  and  quickly  return  on  themselves  when 


342  GENERAL  ANATOMY. 

they  have  yielded,  either  to  distention  or  to  pressure;  it  is 
particularly  when  they  are  compressed  that  their  elasticity  is 
most  remarkable.  They  resist  more  than  the  bones  and  car- 
tilages, the  destructive  action  of  pulsatile  tumours.  In  aneu- 
risms of  the  aorta,  the  vertebrae  are  worn  and  destroyed  before 
the  fibre-cartilage  which  separates  them.  This  property  is  a 
consequence  of  their  elasticity.  The  vital  properties  of  the 
fibro-cartilages  are  obscure,  like  those  of  the  ligamentous  tissue 
generally. 

§  535.  In  their  formation,  several  of  these  parts  pass  through 
the  fibrous  state ;  others  pass  directly  from  the  mucous  to  the 
fibro-cartilaginous  state.  It  is  only  accidentally,  and  in  a  va- 
riable manner,  that  the  permanent  fibro-cartilages  become 
bony  in  old  age;  this,  however,  occurs  more  frequently  to 
them  than  to  the  ligaments,  but  less  frequently  than  to  the 
cartilages. 

§  536.  The  temporary  fibro-cartilages  have  for  use  to  serve 
as  a  type  or  mould  to  bones.  Those  which  are  permanent, 
sometimes  form  flexible,  elastic,  and  very  firm  bonds,  and 
sometimes  serve  to  facilitate  slidings,  by  the  consistency  which 
they  give  to  the  surface. 

§  537.  The  morbid  states  of  the  fibro-cartilages  are  little 
known.  They  unite  again  after  being  divided,  as  is  observed 
after  the  operation  of  symphyseotomy. 

Their  accidental  production  is  not  of  very  rare  occurrence. 
The  centre  of  an  intervertebral  ligament  may  be  taken  as  the 
type  of  the  species,  and  as  an  object  of  comparison.  The  ac- 
cidental fibro-cartilages  are,  in  fact,  fibres,  like  the  ligaments, 
of  a  milky  white  like  the  cartilages,  pliant,  moist  and  elastic. 
According  to  their  form,  connexion  and  uses,  the  accidental 
fibro-cartilages  may  be  divided  into  two  kinds.  Some  are  the 
means  of  union  of  certain  fractures  which  have  not  been  con- 
solidated, either  on  account  of  motions,  like  those  of  the  neck 
of  the  femur,  the  patella  and  others,  or  on  account  of  an  ex- 
tensive loss  of  substance  in  one  of  the  bones  of  the  fore-arm, 
leg,  metacarpus,  skull,  &c.  places  where  the  fragments  can  not 
be  brought  together.  Other  fibro-cartilages  are  formed  on  the 
extremity  of  amputated  bones,  on  the  surfaces  of  supernume- 


OP  THE  FIBRO-CARTILAGINOUS  TISSUE.  343 

rary  articulations,  on  and  about  the  surface  of  the  supplementary 
articular  cavities,  and  in  some  false  anchyloses.  Some  shape- 
less fibro-cartilages  are  found  in  some  compound  tumours  of 
the  thyroid  body,  in  certain  cysts,  and  in  some  cicatrices, 
especially  those  which  occur  in  the  lungs,  after  discharge  of 
tubercles.  Layers  of  the  same  kind  are  found  at  the  surface 
of  the  spleen.  The  fibrous  bodies  of  the  uterus  are  sometimes 
soft  and  pulpy  at  the  centre,  like  the  intervertebral  ligaments. 
Finally,  we  sometimes  find  globular  and  regular  fibro-cartila- 
ginous  masses,  which  freely  float  in  the  serous  cavity  in  which 
they  penetrate.  Dr.  Trouv6,  of  Caen,  gave  me  a  tumour  of 
this  kind,  as  large  as  a  walnut,  which  was  found,  together  with 
another  of  the  same  nature,  in  the  peritoneal  cavity.  This 
tumour,  which  is  distinctly  fibrous  at  the  exterior,  is  soft  like 
the  intervertebral  ligaments  towards  the  centre,  and  contains 
in  this  place  a  bone  of  the  size  of  a  pea. 

§  538.  The  inflammation  of  the  fibro-cartilages  has  been  but 
slightly  observed.  All  we  know  is,  that  in  certain  cases,  the 
desmo-cartilaginous  parts  become  extremely  soft  in  conse- 
quence of  an  afflux  of  fluids,  that  is,  by  a  kind  of  congestion. 
This  is  observed  in  gestation,  at  the  symphysis  of  the  pelvis, 
and  which  has  been  observed  even  in  man,  in  the  same  arti- 
culations. The  vertebral  column  presents  this  softening  in  a 
very  marked  degree  in  cases  of  rachitis.  There  results  from 
it  a  flexibility  of  the  intervertebral  ligaments,  which  makes 
the  column  bend  with  the  greatest  facility,  and  should  the  in- 
dividual keep  himself  habitually  in  an  improper  attitude, 
causes  the  spine-to  bend  laterally  in  several  places,  and  ulti- 
mately involves  the  vertebrae  themselves  in  the  deformity. 

One  of  the  varieties  of  the  vertebral  diseases  also  consists 
in  the  softening  and  swelling  of  the  intervertebral  ligaments, 
which  at  length  ulcerate  and  are  destroyed. 
45 


344  GENERAL  ANATOMY. 


CHAPTER  VII. 


OP  THE  CARTILAGES. 

§  539.  The  cartilages  X6v5pot,  are  white,  hard,  flexible,  very 
elastic,  brittle  parts,  apparently  homogeneous,  which  form  the 
skeleton  of  the  vertebrate  animals  lowest  in  the  series,  (the 
chondropterygious  fishes);  which  in  the  beginning  of  the  life 
of  other  vertebrate  animals  fulfil  the  functions  of  bones;  some 
of  which  remaining  in  the  adult  age,  form  parts  which  are 
solid,  hard,  and  flexible  at  the  same  time. 

§  540.  The  old  anatomists  and  those  of  the  Italian  school, 
disputed  much  respecting  the  matter  which  forms  the  bones 
and  cartilages,  and  about  their  differences;  Galiardi  and  Ha- 
vers in  vain  sought  for  this  difference  in  the  intimate  texture 
of  the  parts.  More  useful  observations  have  been  made  in 
the  last  century  on  the  cartilaginous  tissue.  We  are  indebted 
to  Haase*  for  a  very  good  dissertation  on  this  subject;  but 
this  anatomist,  like  several  of  those  who  preceded  and  fol- 
lowed him,  has  confounded  the  condroid  ligaments  with  the 
cartilages,  which  renders  his  general  description  rather  vague. 
Bichat  has  separated  from  the  other  cartilages  those  which 
are  thin  and  very  flexible,  to  form  together  with  the  cartila- 
giniform  ligaments,  the  fibro-cartilaginous  system;  but  these 
latter  are  in  fact  ligaments,  and  the  former  true  cartilages. 

§  541.  The  cartilages  are  either  temporary  or  permanent: 
the  former  constantly,  completely  and  regularly  disappear  at 
a  determinate  period  of  their  growth,  and  are  replaced  by  the 
bones;  the  latter  remain  a  much  longer  time,  and  sometimes 
more  than  a  century,  in  the  cartilaginous  state;  however, 

*  J.  G.  Haase,  de  Fabrlca  cartilaginum.   Lips.  1767. 


OP  THE  CARTILAGES  IN  GENERAL.  345 

several  of  them,  at  least  ossify,  sometimes  even  at  the  end 
of  the  period  of  growth.  The  temporary  cartilages  will  be 
described  along  with  the  bones,  (chap,  viii.)  We  shall  treat 
here  only  of  the  cartilages  called  permanent:  they  form  a 
very  natural  genus  of  organs,  and  present  also  some  differences. 


SECTION  I. 

OF  THE  CARTILAGES  IN  GENERAL. 

§  542.  Some  cartilages  have  an  elongated  form :  such  are 
the  cartilages  of  the  ribs ;  others  are  thick  and  short,  like  the 
arythenoid  and  cracoid  cartilages;  but  the  greater  number  are 
broad  and  thin. 

Some  are  attached  to  the  bones  of  which  they  cover  certain 
parts;  others  are  prolongations  of  them  and  are  firmly  united 
to  them;  others  are  connected  to  the  bones  by  ligaments; 
others  are  attached  to  each  other,  and  have  no  other  connexions 
with  the  bones. 

The  cartilages  are  of  a  pearly  white,  and  semi-transparent 
when  in  their  laminae;  although  they  are  the  hardest  parts  of 
the  body  after  the  bones,  they  are  easily  cut. 

§  543.  The  cartilages,  when  examined  in  their  substance, 
present  neither  cavities,  nor  canals,  nor  areolae,  nor  fibres, 
nor  laminae,  finally,  nothing  that  indicates  an  organic  texture; 
they  appear  homogeneous.  It  seems,  however,  that  they  have 
a  distinct  and  different  kind  of  texture  in  each  species  of  carti- 
lage: this  assertion  will  be  investigated  hereafter. 

All  the  cartilages,  with  the  exception  of  those  of  the  articu- 
lar surfaces,  are  enveloped  in  a  fibrous  membrane,  the  peri- 
chondrium,  whicli  has  few  vessels,  and  is  not  so  intimately 
connected  with  the  cartilages  as  the  periosteum  is  with  the 
bones.  Neither  nerves  nor  vessels  have  ever  been  discovered 
in  the  cartilages;  the  cellular  tissue  is  not  apparent  during  life, 
and  after  death  they  require  to  be  macerated  during  several 
months,  even  with  young  subjects,  to  reduce  them  to  a  mu- 


346  OENERAL  ANATOMY. 

cous  substance  analogous  to  the  cellular  tissue,  and  which,  in 
their  ordinary  state,  must  be  an  extreme  degree  of  compact- 
ness and  condensation. 

§  544.  Cartilages  contain  a  great  quantity  of  water*  or  se- 
rous liquid,  which  oozes  at  the  surface  when  it  is  cut,  and 
which  moistens  it.  In  the  adult  man  the  proportion  of  water 
that  they  contain  is  to  the  solid  substance  as  2i  is  to  1.  Dried 
cartilages  become  semi-transparent,  yellowish,  and  susceptible 
of  being  torn;  steeped  in  water  it  resumes  in  four  days  its 
weight  and  volume,  its  white  colour,  its  flexibility,  and  partly 
loses  its  transparency. 

§  545.  Submitted  to  the  action  of  boiling  water  when  in  thin 
lamina?,  it  at  first  crisps  them  and  renders  them  yellow  and 
opaque. 

The  prolonged  action  of  the  boiling  water  on  cartilages  es- 
tablishes between  them  a  difference  founded  also  on  other 
character;  the  cartilages  of  the  joints  are  reduced  into  a  jelly 
by  decoction,  the  other,  on  the  contrary,  resist  its  action.  Al- 
cohol renders  cartilages  slightly  opaque.  Diluted  acids  have 
no  action  upon  them ;  when  concentrated,  they  act  as  upon 
the  epidermis.  Their  chemical  analysis  is  as  yet  imperfect. 
It  has  been  vaguely  repeated,  after  Haller,  that  they  are  com- 
posed of  gelatine  and  earth.  According  to  M.  Allen,  they  are 
composed  of  gelatine,  and  a  hundredth  of  carbonate  of  lime. 
Hatchett  says  that  they  are  formed  of  coagulated  albumen  and 
traces  of  phosphate  of  lime ;  but  we  do  not  know  to  which 
cartilages  he  alludes.  M.  Chevreul  has  found  that  the  cartila- 
ginous bones  of  the  shark  (sgualus)  are  composed  of  oil,  mu- 
cus, acitic  acid,  and  some  salts.  J.  Davy  has  found  cartilages 
formed  of  albumen  44, 5;  water  55;  and  phosphate  of  lime  0,  5. 

§  546.  The  physical  property  the  most  remarkable  of  the 
cartilages  is  elasticity.  They  do  not  elongate  and  return  on 
themselves,  like  the  elastic  tissue;  they  generally  do  not  yield 
to  pressure,  like  the  chondroid  ligaments,  and  afterwards  re- 
sume their  thickness;  but  they  are  flexible,  and  return  to  their 

*  Chevreul,  de  f  influence  gue  Feau  exerce,  &c.  Jlnnaks  de  Chimie  et  de 
Physique,  tome  19. 


OP  THE  CARTILAGES  IN  GENERAL.  347 

general  former  state  with  force  and  celerity  whenever  the  cause 
of  flexion  ceases  to  act.  The  articular  cartilages  alone  are  elas- 
tic in  the  same  manner  as  the  fibre-cartilaginous  tissue. 

§  547.  The  vital  properties  and  phenomena  of  formation, 
irritation  and  sensation,  are  extremely  obscure  in  the  cartila- 
ginous tissue.  It  is  not  known  if  the  pain  felt  in  the  articula- 
tion, and  caused  by  foreign  bodies  when  between  the  two  sur- 
faces, is  to  be  ascribed  to  the  articular  cartilages,  or  rather  to 
the  synovial  membrane  which  invests  them. 

§  548.  The  functions  of  the  cartilages  depend  solely  upon 
Iheir  physical  properties;  upon  their  firmness,  which  enables 
them  to  preserve  the  shape  of  certain  parts ;  upon  their  flexi- 
bility and  elasticity,  which  permit  them  to  yield,  at  times,  and 
resume  afterwards  their  former  state. 

§  549.  The  cartilages  in  the  embryo  and  foetus,  are  at  first 
soft,  mucous  and  transparent,  like  jelly  or  glue;  the  propor- 
tion of  water  at  this  time  is  very  great ;  in  the  child,  they  are 
yet  slightly  coloured,  very  transparent,  very  soft,  and  slightly 
elastic.  They  afterwards  become  white,  acquire  firmness,  and 
the  semi-opacity  which  characterizes  them.  Later,  in  old  age, 
they  become  whiter  or  yellower,  more  opaque,  less  flexible, 
less  elastic,  more  brittle  and  drier;  the  proportion  of  water  di- 
minishes, and  that  of  the  earthy  substance  increases.  They 
at  last  ossify,  at  least  in  some  points.  This  alteration  com- 
mences sometimes  as  soon  as  the  adult  age,  but  especially  in 
old  age.  Inflammation  prematurely  determinates  this  change. 

§  550.  The  organic  action  of  nutrition  seems  to  be  very  slow 
in  it.  The  use  of  madder  does  not  colour  them  ;  that. substance 
appears  to  have  affinity  only  with  the  earthy  substance  of 
bones.  They  become  yellow  in  jaundice.  The  cartilaginous 
bones  of  the  vertebral  column  of  the  lamprey  appear  and  dis- 
appear every  year,  from  which  they  must  be  inferred  to  pos- 
sess a  great  organic  activity,  which  is  also  the  case  with  the 
rapid  growth  of  the  larynx  towards  the  period  of  puberty. 

§  551.  Accidental  cartilaginous  productions  are  very  com- 
mon, they  have  all  the  characters  of  natural  cartilages:  colour, 
apparent  homogeneity,  £c.  They  present  all  the  varieties  of 
texture  of  the  cartilages,  and  even  more;  we  must  therefore 


34S  GENERAL  ANATOMY. 

divide  them  into  two  kinds.  The  imperfect  accidental  car- 
tilages are  sometimes  in  the  state  of  jelly,  or  have  the  consist- 
ence of  the  boiled  white  of  egg.  They  have  a  milky,  or  yel- 
lowish, or  pearly-gray  colour;  they  are  partially  or  totally  os- 
sified, rather  than  becoming  perfect  cartilages.  They  are  met 
with  under  the  form  of  incrustations  in  the  arteries,  and  espe- 
cially in  the  aorta  and  in  the  cerebral  arteries;  under  the  form 
of  cysts  around  morbid  productions  and  acephalocysts;  forming 
the  fistulous  passages  in  the  lungs;  under  the  form  of  irregular 
masses  in  goitres,  and  other  compound  tumours,  and  under 
that  of  isolated  bodies  in  the  articulations. 

The  perfect  accidental  cartilages  are  those  which  present  the 
character  of  the  natural  tissue,  and  especially  its  firmness. 
Some  are  found  forming  small  cysts  filled  with  phosphate  of 
lime.  Some  are  sometimes  met  with  in  the  state  of  isolated 
bodies,  of  a  moderate  volume  of  an  obround  figure,  in  the  syno- 
vial  membranes,  or  at  their  exterior,  whence  they  penetrate 
into  the  cavity  by  pushing  the  membrane  before  them,  enve- 
loping itself  as  with  the  finger  of  a  glove  whose  base,  after  be- 
coming very  thin,  separates.  They  imperfectly  ossify  either 
in  part  or  in  totality,  but  beginning  in  the  centre.  These  car- 
tilaginous bodies  are  also  found  in  the  splanchnic  cavities,  and 
especially  in  the  tunica  vaginalis,  into  which  they  penetrate 
like  those  just  described. 

Perfect  cartilages  also  occur  under  the  form  of  incrustations 
or  plates,  in  the  sub-serous  cellular  tissue  of  the  spleen,  the 
lungs,  and  the  pleura  costalis,  in  the  substance  of  the  valves  of 
the  heart,  especially  in  the  left  side,  in  the  sub-serous  tissue  of 
the  diaphragmatic  pleura  and  peritoneum,  and  in  that  of  the 
liver  in  hernise,  and  seldom  in  the  anterior  parietes  of  the  ab- 
domen. All  these  incrustations  have  a  great  tendency  to  ossify. 
Cartilages  also  happen  in  shapeless  masses  in  the  compound 
tumours, under  the  accidental  cellular  tissue  of  the  serous  mem- 
branes. 

Accidental  cartilages  are  sometimes  formed  by  transforma- 
tion of  other  tissues.  An  old  woman  who  some  years  ago 
was  at  the  Hospital  of  the  faculty  of  medicine  at  Paris,  and 
who  had  on  her  forehead  a  broad  conoid  horny  production 


OF  THE  DIFFERENT  KINDS  OF  CARTILAGES.  349 

which  grew  on  the  cicatrix  of  a  burn,  having  died,  the  bones 
of  the  skull  immediately  under  this  horn  were  found  to  be 
transformed  into  cartilages.  Laennec  saw  a  cartilaginous  trans- 
formation of  the  mucous  membrane  of  the  urethra.  I  have 
observed  the  same  thing  in  the  vagina,  in  a  case  of  prolapsus 
uteri,  and  in  the  prepuce,  in  a  case  of  congenital  phymosis, 
in  an  old  man.  I  am  at  the  same  time  of  opinion  that  these 
three  cases  belong  rather  to  the  desmo-cartilaginous  produc- 
tions. 

§  552.  Alterations*  of  the  cartilages  are  rare  and  most  com- 
monly consecutive.  They  resist  for  a  very  long  time  the 
destructive  action  of  aneurismal  tumours,  and  the  propagation 
of  diseases  of  the  neighbouring  parts.  The  alterations  to 
which  the}7  are  subject,  and  the  reparation  of  their  injuries, 
are  somewhat  different  in  the  various  kinds  of  this  tissue. 


SECTION  II. 

OF  THE  DIFFERENT  KINDS  OF  CARTILAGES. 

§  553.  The  cartilages  may  be  divided  into  three  principal 
kinds,  with  respect  to  their  form,  connexions,  texture,  pro- 
perties and  functions. 

ARTICLE  I. 
A.    OF  THE  ARTICULAR  CARTILAGES. 

§  554.  The  diarthrodial  articular  cartilagest  are  flat  and 
broad  cartilaginous  laminae,  which  tip  or  invest  the  surfaces 
of  the  bones  in  the  moveable  articulations.  These  laminae 

*  Doerner,  praeside  Autenrieth,  de  Gravioribus  quibusdam  cartilaginum 
mutationibus.  Tubing.  1798. 

|W.  Hunter,  Of  the  structure  and  diseases  of  articulating  cartilages;  in 
Philos.  trans.  1743. — Delasone,  sur  V organisation  dcs  os;  mem.  de  Facad.  des 
sd.  Paris,  1752. 


350  GENERAL  ANATOMY. 

have  a  free  surface,  covered  by  the  synovial  membrane  which 
is  closely  attached  to  it,  and  a  surface  which  also  adheres  in- 
timately to  the  surface  of  the  bone,  without  a  continuity  of 
tissue  however  existing  between  them.  Their  circumference, 
which  is  thinner  than  the  rest,  extends  to  that  of  the  articular 
surfaces  of  the  bones.  Their  thickness,  which  is  inconsidera- 
ble and  proportionate  to  their  breadth,  is  from  one  to  two 
lines  in  the  largest,  and  a  fraction  of  a  line  in  the  smallest. 
It  is  not  the  same  in  the  whole  of  their  extent.  Those  which 
incrust  or  tip  convex  bony  surfaces  are  thicker  at  the  centre 
than  in  the  remainder  of  their  extent.  Those  of  the  concave 
surfaces,  on  the  contrary,  are  thicker  at  the  circumference 
than  at  the  centre. 

§  555.  The  texture  of  these  cartilages  is  at  first  sight  as  in- 
distinct as  that  of  the  others,  so  that  they  resemble  a  layer  of 
wax  spread  over  the  bone,  but  may  be  discovered  by  certain 
modes  of  procedure,  it  is  fibrous.  Maceration  of  an  articu- 
lar part  of  a  bone,  continued  for  six  months,  effects  the  de- 
struction of  the  synovial  membrane,  the  only  membrane  co- 
vering the  cartilage  which  is  destitute  of  the  fibrous  perichon- 
drium,  and  produces  disunion  of  the  fibres  of  which  it  is 
composed,  which  rise  perpendicularly  from  the  surface  of  the 
bone  like  the  pile  of  velvet.  If  a  cartilage  thus  disposed  by 
maceration  be  dried,  the  fibres  become  smaller  and  thus  sepa- 
rate from  each  other,  becoming  more  distinct.  Decoction, 
when  not  prolonged  so  as  to  dissolve  the  cartilage,  produces 
at  first  the  same  effect  as  maceration.  The  action  of  fire  also 
discloses  the  structure  in  the  same  manner.  These  cartilages 
have  no  vessels.  Delicate  injection  and  microscopic  inspec- 
tion show  the  capillary  vessels  terminating  at  their  circumfer- 
ence and  at  their  adherent  surface,  without  ever  penetrating 
into  their  substance. 

These  cartilages,  which  are  compressible  and  elastic,  deaden 
the  effects  of  pressure  and  concussions.  The  smoothness  of 
their  surface  facilitates  the  motion  of  the  diarthrodial  articula- 
tions. They  become  much  thinner  in  old  age. 

§  556.  In  preternatural  joints,  no  true  cartilages  are  pro- 
duced, but  only  desmo-chondroid  tissue,  a  tissue  which,  in 


OP  THE  ARTICULATE  CARTILAGES.        351 

truth,  greatly  resembles  that  of  the  diarthrodial  cartilages.  In 
the  natural  diarthrodial  articulations,  the  destruction  of  the 
cartilages  is  sometimes  followed  by  their  nearly  perfect  re- 
production ;  only  the  new  cartilage  produced  at  the  surface  of 
the  bone,  being  thinner,  has  a  somewhat  bluish  appearance, 
which  is  owing  to  its  semi-transparency.  The  edges  of  the 
old  cartilage  are  free,  and  extend  over  the  very  thin  contour  of 
the  new  cartilage. 

In  the  joints  of  old  persons  affected  with  various  other  al- 
terations, the  diarthrodial  cartilages  are  sometimes  found  con- 
verted into  villous  fibres,  free  and  floating.  When  laid  bare 
in  amputation  at  the  joints,  if  the  wound  unites  by  first  inten- 
tion, the  cartilage  and  its  synovial  membrane  do  not  unite, 
but  remain  free  behind  the  cicatrix.  If  the  wound  remains 
open,  if  it  inflames  and  suppurates,  the  cartilage  is  seen  at  the 
end  of  some  days  to  soften,  and  afterwards  gradually  to  disap- 
pear from  the  circumference  to  the  centre,  in  proportion  as 
the  granulations  extend  to  the  surface  of  the  bone,  and  even 
before  they  reach  it.  Inflammation  of  the  diarthrodial  carti- 
lages is  in  general  of  rare  occurrence;  and,  when  it  takes 
place,  commonly  terminates  by  ulceration  or  absorption.  This 
ulceration  of  the  diarthrodial  cartilages  is  most  commonly 
consequent  to  inflammation  of  the  synovial  membrane  or  bone, 
sometimes  to  that  of  the  cartilage  itself,  but  it  also  sometimes 
seems  not  to  be  preceded  by  any  inflammation.  Sometimes, 
before  ulcerating,  the  cartilage  softens  and  assumes  a  fibrous 
appearance.  This  ulceration  most  commonly  takes  place  in 
young  subjects,  or  before  middle  age.  It  is  accompanied  by 
a  pain,  which  is  at  first  slight,  but  which  gradually  increases 
in  intensity.  When  the  ulceration  stops  and  heals,  there 
takes  place  a  reproduction  of  cartilage,  of  which  we  have  al- 
ready spoken,  or  a  bony  production  of  the  nature  of  ivory 
or  enamel,  or,  lastly,  a  union  of  the  surfaces  by  anchylosis. 
In  the  case  of  true  anchylosis,  the  cartilages  are  always  ab- 
sorbed. 

§  557.  The  cartilages  of  the  synarthrodial  articulations,  are 
extremely  thin  laminae,  placed  between  the  bones  which  are 
articulated  in  an  immoveable  manner,  and  holding  firmly  on 


352  GENEBAL  ANATOMY. 

each  side  to  these  bones  hy  a  kind  of  suture.  Their  edges,  in 
the  interval  between  the  bones,  are  intimately  attached  to  ex- 
ternal and  internal  periosteum,  which  passes  from  the  one  to 
the  other  bone.  Thus  they  greatly  contribute  to  the  solidity 
of  these  articulations.  These  cartilages,  in  the  sutures  of  the 
skull,  are  thinner  at  the  interior,  than  at  the  exterior  of  the 
wall,  which  in  pa-rt  accounts  for  the  quicker  disappearance  of 
the  sutures  at  the  interior  than  at  the  exterior  of  the  skull. 
With  respect  to  the  frequency  of  their  ossification,  they  are 
intermediate  between  the  temporary  and  the  permanent  car- 
tilages. 


ARTICLE  II. 
OF  THE  COSTAL,  LARYNGEAL,  AND  OTHER  CARTILAGES. 

§  558.  The  costal  cartilages*  are  the  longest  and  thickest 
cartilages  of  the  body.  They  constitute  cartilaginous  prolon- 
gations to  the  bony  ribs.  The  first  of  them  may  also  be  con- 
sidered as  anterior  or  sternal  cartilaginous  ribs.  The  cartilages 
are  all  attached  to  the  anterior  extremities  of  the  ribs,  like  the 
synarthrodial  cartilages.  The  first  is  even  continuous  with 
the  sternum  at  the  other  extremity.  The  next  six  are  articu- 
lated with  the  sternum  by  diarthrosis.  The  three  following 
are  in  the  same  manner  articulated  with  those  which  precede 
them.  The  last  two  are  immersed  in  the  intermuscular  cellu- 
lar tissue. 

§  559.  The  texture  of  these  cartilages  is  very  obscure,  and 
at  first  sight  they  appear  homogeneous.  However,  by  macera- 
tion prolonged  for  at  least  six  months,  the  costal  cartilages  di- 
vide into  oval  laminae  or  plates,  separated  from  each  other  by 
circular  or  spiral  lines;  and  united  together  by  some  oblique 
fibres  which  they  send  into  each  other.  These  laminae  are 
themselves  divided  into  radiated  fibrils,  and  the  fibrils  at  length 
into  minute  bundles,  which  are  at  length  reduced  into  mucous 

*  Heissant,  Sur  la.  structure  des  cartilages  des  cotes  de  Fkomme  et  du  cheval, 
in  M£m.  de  1'acad.  des  sc.,  1748. 


OF  THE  COSTAL  AND  LARYNGEAL  CARTILAGES.  353 

substance.  All  these  divisions  or  separations  are  first  pro- 
duced at  the  circumference  of  the  cartilage.  The  centre  is 
more  homogeneous,  and  is  the  last  part  that  divides.  This 
separation  may  be  accelerated  by  drying  in  the  sun  a  costal 
cartilage  that  has  been  macerated  for  two  or  three  months. 
Acids  produce  a  similar  effect. 

§  560.  The  costal  cartilages  are  somewhat  flexible  and  high- 
ly elastic.  In  inspiration,  the  motion  impressed  upon  the  ribs 
by  the  muscles,  bends  them  and  twists  them  upon  themselves; 
and  when  the  muscular  action  ceases,  they  spontaneously  re- 
sume their  original  direction,  and  are  thus  agents  of  expira- 
tion. 

§  561.  After  adult  age,  and  in  old  age,  the  costal  cartilages 
cease  to  be  or  to  appear  homogeneous.  Their  perichondrium 
becomes  opaque,  and  there  are  produced,  between  it  and  the 
cartilage,  and  in  its  substance,  bony  plates,  more  or  less  nu- 
merous and  broad,  which  sometimes  end  with  forming  a  more 
or  less  complete  bony  sheath.  This  change  almost  always 
happens  to  the  first,  commencing  at  its  sternal  extremity.  The 
other  sterno-costal  cartilages  also  experience  it,  but  in  a  less 
degree.  The  asternal  costal  cartilages,  or  those  of  the  false 
ribs,  experience  it  still  less,  or  not  at  all.  At  the  same  time 
the  costal  cartilages  become  yellowish,  then  reddish  in  their 
centre,  which  also  presents  more  or  less  large  and  numerous 
bony  points,  which  sometimes  at  length  occupy  the  whole  car- 
tilage. This  latter  phenomenon  shows  itself  more  frequently 
and  sooner  in  the  asternal  cartilages  than  in  the  others. 

These  changes  in  the  cartilages  are  commonly  the  effect  of 
age.  They  commence  towards  the  middle  of  life,  and  go  on 
continually  increasing.  Persons  of  a  hundred  and  thirty  and 
a  hundred  and  fifty  years,  however,  have  been  seen  to  have 
costal  cartilages  in  their  natural  state. 

When  the  cartilages  begin  to  undergo  this  change,  desicca- 
tion causes  them  to  break  across  in  the  centre,  which  has  be- 
come areolar,  and  not  at  the  surface,  which  has,  on  the  con- 
trary, become  denser. 

They  frequently  ossify,  and  at  an  early  age,  in  persons 
affected  with  phthisis, 


354  GENERAL  ANATOMY. 

§  562.  The  costal  cartilages,  when  denuded,  do  not  produce 
granulations,  but  are  covered  by  those  of  the  neighbouring 
parts.  When  broken,  they  do  not  unite  by  a  cartilaginous 
substance,  but  a  cellular  lamina  is  produced  between  them, 
and  the  broken  place  is  enveloped  with  a  bony  ring  furnished 
by  the  perichondrium,  and  which  is  more  or  less  regular,  ac- 
cording as  the  fragments  have  remained  more  or  less  exactly 
in  opposition.  I  have  sometimes  seen  in  man,  and  repeatedly 
in  the  horse,  the  fractures  of  ossified  asternal  cartilages,  united 
by  a  bony  callus. 

The  costal  cartilages  are  subject  to  some  vices  of  original 
conformation,  and  are  even  liable  to  be  wanting  in  whole  or 
in  part.  In  the  latter  case,  it  is  always  the  extremity  next  to 
the  rib  that  exists.  When  the  thorax  is  deformed,  when  it  is 
contracted,  as  sometimes  happens  after  the  cure  of  pleurisy, 
the  cartilages  of  the  affected  side  bend  and  become  deformed. 

§  563.  The  nasal  cartilage,  that  of  the  auditory  canal,  and 
that  of  the  Eustachian  tube,  are  in  a  manner  articulated  with 
the  bones.  Those  of  the  larynx,  on  the  contrary,  are  only 
attached  to  the  bones  by  ligaments,  and  are  connected  together 
by  moveable  articulations. 

These  cartilages  have  still  a  certain  thickness.  When  their 
perichondrium  is  raised,  their  surface  is  found  to  be  smooth 
and  compact.  Long  continued  maceration  divides  these  carti- 
lages into  soft  and  short  fibres  or  filaments.  Decoction  and  mi- 
neral acids  produce  the  same  effects. 

These  cartilages  are  flexible  and  elastic.  By  their  solidity 
they  preserve  the  form  and  cavity  of  the  organs  which  they 
contribute  to  form.  Those  of  the  larynx  present  the  remark- 
able peculiarity  of  a  very  rapid  growth  at  the  period  of  puber- 
ty. These  same  cartilages  sometimes  ossify  from  the  adult 
age,  at  least  in  part.  Chronic  inflammation  of  the  mucous 
membrane  of  the  larynx,  and  its  ulceration,  greatly  hasten 
this  ossification,  which,  in  fact,  always  takes  place  in  phthisis 
laryngea,and  is  of  frequent  occurrence  in  phthisis  pulmonalis. 

When  the  thyroid  and  cricoid  cartilages  are  divided,  they 
unite  by  bony  laminae  of  the  perichondrium,  which  are  thicker 
at  the  exterior  than  at  the  interior  of  the  larynx. 


OF  THE  MEMBRANIFORM  CARTILAGES.  355 

ARTICLE  III. 
OF  THE  MEMBRANIFORM  CARTILAGES. 

§  564.  The  membraniform  cartilages  are  those  which  Bichat 
has  placed  in  his  fibro-cartilaginous  system.  They  are  very 
thin,  and  possessed  of  great  flexibility. 

They  are  the  palpebral  cartilages  or  tarsi,  the  cartilage  of 
the  ear,  those  of  the  nostrils,  the  cartilage  of  the  epiglottis, 
the  median  cartilage  of  the  tongue,  and  the  cartilages  of  the 
trachea  and  bronchi. 

These  very  thin  cartilages  are  furnished  with  a  perichondri- 
um,  which  is  very  thick  and  very  strong  compared  with  them- 
selves, and  sends  into  their  substance  fibrous  and  cellular  pro- 
longations, some  of  which  even  pass  entirely  through  them. 
Their  surface  also  is  very  uneven  and  porous.  Maceration 
continued  for  two  or  three  months  softens  them,  and  reduces 
them  to  the  state  of  distinct  fibrils  at  first,  and  finally  into  cel- 
lular or  mucous  substance. 

They  are  very  flexible,  perfectly  elastic,  and  much  less 
brittle  and  more  tenacious  that  the  other  cartilages.  Like  the 
preceding,  they  concur  in  forming  organs  or  canals,  of  which 
they  preserve  the  form  and  caliber.  They  are  rarely  ossified, 
and  only  at  a  very  advanced  period  of  life.  The  rings  of  the 
trachea  alone  present  a  more  or  less  extended  ossification  in 
the  adult.  In  cases  of  phthisis,  however,  the  cartilaginous 
arches  of  the  bronchi  have  been  found  ossified.  In  gouty  per- 
sons also,  and  after  inflammation  of  the  ear,  the  cartilage  of 
that  part  has  been  seen  to  become  bony.  In  the  case  of  goitre, 
and  even  without  this  cause  of  pressure,  the  cartilaginous  rings 
of  the  trachea  are  sometimes  found  compressed  from  one  side 
to  the  other,  and  their  middle  part  bent  at  an  angle.  The  same 
change  of  form  is  also  observed  in  the  bronchi. 


356  GENERAL  ANATOMY. 


CHAPTER  VIII. 


OF  THE  OSSEOUS  SYSTEM. 

§  565.  The  osseous  system,*  or  the  skeleton,  2%fMiw,  re- 
sults from  the  union  of  the  bones,  which  are  the  hardest  and 
driest  parts  of  the  body. 

§  566.  It  is  of  all  the  systems  that  which  shows  itself  last 
in  the  animal  series;  it  appears  along;  with  the  nervous  centre 
(the  spinal  marrow  and  brain)  to  which  it  serves  as  an  enve- 
lope. 

§  567.  The  same  sense  has  not  always  been  attached  to  the 
words  bone  and  skeleton.  In  the  writings  of  Hippocrates  and 
Aristotle  is  found  the  source  of  the  two  principal  ideas  at- 
tached to  these  words,  and  which  are  still  a  subject  of  contro- 
versy among  zootomists. 

The  author  of  the  Treatise  on  the  Nature  of  the  Bones  at- 
tributes to  them  the  uses  of  determining  the  form,  the  straight- 
ness,  and  the  direction  of  the  body.  This  idea  has  prevailed, 
and  it  is  still  generally  admitted,  that  the  principal  functions 
of  the  osseous  system  are  to  determine  the  form  of  the  body, 
and  to  facilitate  its  motions.  Agreeably  to  this  definition, 

*  The  best  works  on  osteology  are  the  following: — A.  Monro,  Anatomy 
of  the  Bones  and  Nerves.  Edin.  1726,  8vo. — W.  Cheselden,  Osteographiat 
&c.  Lond.  1733.  fol. — B.  S.  Albinus,  de  Os&ibus  carp.  hum.  Lugd.  Bat. 
1726,  8vo.— Id.  de  Scekto  hum.  ibid.  1762.  4to.— Id.  Tab.  sceleti  et  muscul. 
ibid.  1747.  fol.  max.— Id.  Tab.  ossium.  ibid.  1753.  fol.  max.— Boehmer. 
Institutiones  osteologicce.  Halac-Magd.  1751. — Tarin.  Osteographie.  Paris, 
1753.— Bertin.  Traitt  tfosteologie.  Paris,  1754.  Ed.  Sandifort.  Descrip- 
tio  ossium  hominis.  Lugd.  Bat.  1785. — Loschge.  Die  Knochen,  &c.  Ab- 
bildungen  und  kurzen  Beschr.  Erlang.  1804.  fol.  Blumenbach.  Getchichtc 
und  Btschreibung  der  Knochen.  Getting.  1807. 


OP  THK  OSSEOUS  SYSTEM.  357 

the  hard  parts  of  the  other  articulated  animals,  and  especially 
those  of  the  insecta  and  Crustacea,  ought  to  have  been  assimi- 
lated to  the  bones,  for  it  is  in  the  latter  that  voluntary  motion 
and  the  preservation  of  the  form  of  the  body  are  carried  to  the 
highest  pitch.  Willis,  in  speaking  of  the  crab,  uses  the  fol- 
lowing words: — Quo  ad  membra  etpartes  matrices,  non  ossa 
teguntur  carnibus,  sed  carries  ossibus. 

Aristotle,  however,  who  already  considered  the  spine  as  the 
origin,  or  centre,  from  which  the  bones  are  derived,  had  giv- 
en the  first  intimation  respecting  the  distinction  which  has  in 
these  latter  times  been  made  between  the  bones  and  the  other 
hard  parts  of  animals.  According  to  this  idea,  the  skeleton, 
or  osseous  system  of  the  vertebrate  animals  is,  in  fact,  first, 
and  principally  seen  to  consist  of  a  longitudinal  column,  which 
furnishes  superiorly,  or  posteriorly,  an  envelope  to  the  spinal 
marrow  and  brain,  and  anteriorly,  or  inferiorly,  another  en- 
velope to  the  organs  of  nutrition,  and  especially  to  the  central 
parts  of  the  vascular  system.  Other  less  constant  appendages 
are  subservient  to  motion  through  their  articulations.  All  the 
parts  of  the  system,  besides,  may  furnish  attachment  to  mus- 
cles. 

The  question,  therefore,  is,  whether  all  the  hard  and  dry 
parts  of  the  body  of  animals,  those  which  determine  its  form 
and  facilitate  its  motions,  are  to  be  called  bones  and  skeleton; 
or  if  these  names  are  to  be  restricted  to  the  hard  parts,  pecu- 
liar to  the  vertebrate  animals,  which  form  a  central  and  median 
column  in  the  body,  with  a  cavity  for  the  nervous  trunk,  and 
another  cavity  for  the  heart  and  aorta,  and  frequently  lateral 
appendages  for  motion. 

According  to  M.  GeoffYoi  Saint-Hilaire,  one  of  the  natural- 
ists who  has  engaged  most  deeply  in  the  study  of  this  point 
of  zootomy,  and  who  has  treated  it  with  his  original  talent, 
there  is  no  doubt  on  the  subject,  and  all  the  difference  between 
the  skeleton  of  an  articulate  and  a  vertebrate  animal,  between 
the  rachis  of  a  crustaceous  animal  or  an  insect,  and  that  of  an 
osseous  animal,  depends  upon  the  absence  of  a  spinal  marrow 
in  the  former,  and  its  presence  in  the  latter;  a  difference  which 
renders  necessary  a  rachis  with  two  canals  in  the  vertebrate 


358  GENERAL  ANATOMY. 

animals,  and  one  with  a  single  canal  in  the  crustaceous.  Ac- 
cording to  this  last  idea,  if  I  understand  it  well,  an  insect  or 
a  crustaceous  animal  could  be  correctly  compared  to  a  mon- 
strous vertebrate  animal  deprived  of  brain  and  spinal  marrow. 
§  568.  Be  this  as  it  may,  however,  with  respect  to  this  dif- 
ference of  opinion,  altogether  foreign  to  the  anatomy  of  man, 
there  are  three  things  to  be  considered  in  the  osseous  system; 
the  bones  themselves,  their  articulations,  and  the  skeleton 
which  results  from  their  union. 


SECTION  I. 

OP  THE  BONES. 


§  569.  The  Bones,  Ossa,  Ocr^a,  are  the  hardest  parts  of  the 
human  body,  those  which  by  their  union  form  the  skeleton. 

§  570.  Each  of  the  bones,  and  many  parts  of  bones,  have 
received  particular  names.  These  names  ought  to  be  so  much 
the  more  precise  and  appropriate,  that  the  names  of  many 
other  parts  of  the  body  are  formed  from  them. 

The  name  of  several  bones  is  an  adjective  taken  substan- 
tively  with  a  common  termination:  for  example,  the  frontal, 
occipital,  parietal,  &c.*  M.  Dumerilt  has  proposed,  as  a  means 
of  giving  precision  and  accuracy  to  the  language  of  anatomy, 
to  give  the  same  termination  to  all  the  names  of  bones,  and  to 
them  only. 

§  571.  The  number  of  the  bones  is  very  great,  but  different- 
ly determined,  according  as  we  take  the  subject  at  a  particular 
age,  or  different  subjects  at  different  ages;  and  this  is  what  has 
most  commonly  been  done.  If,  for  example,  it  be  wished  to 
determine  the  number  strictly,  taking  the  adult  subject,  the 
sphenoid  bone  then  occurs  united  to  the  occipital,  and  often  to 
the  ethmoid;  but  the  sternum  is  still  divided  into  three  parts, 

*  This  mode  of  expression  is  correct  in  French,  but  it  is  incorrect  in  Eng- 
lish, and  we  are  obliged  to  say,  the  frontal  bone,  the  occipital  bone,  See. 

TRANS. 

f  Prqfet  (Tune  nomenclature  anatomique,  Magasin  Encyclopedique,  t.  ii. 
Paris,  1795. 


OF  THE  BONES.  359 

and  the  hyoid  bone  is  still  composed  of  at  least  three  distinct 
pieces. 

The  following  is  an  enumeration  of  the  bones  which  most 
anatomists  agree  in  describing  as  distinct. 

Twenty-four  moveable  vertebra. 

Five  pelvic  vertebra^  united  to  form  the  sacrum  or  pelvic 
bone. 

Three  or  four  caudal  vertebras,  united  to  form  the  coccyx. 

Twelve  ribs  on  each  side;  a  single  sternum,  formed  of  three 
distinct  pieces  in  the  adult. 

An  occipital  bone,  a  sphenoid  bone,  an  ethmoid  bone,  a 
frontal  bone,  two  parietal  bones,  two  temporal  bones,  each 
containing  three  ossicula  tympani;  a  vomer,  two  upper  max- 
illar  bones,  two  palate  bones,  two  zygomatic  bones,  two  nasal 
bones,  two  lachrymal  bones  or  ossa  unguis,  two  inferior  tur- 
binated  bones,  an  inferior  maxillar  bone. 

A  hyoid  bone,  composed,  even  in  the  adult,  of  three  or  five 
distinct  pieces. 

The  bones,  which  remain  to  be  enumerated,  are  all  paired, 
or  double,  and  are  those  of  the  limbs  or  extremities;  viz. 

The  scapula,  the  clavicle,  the  humerus,  the  radius,  the  ulna, 
the  eight  bones  of  the  carpus,  the  five  of  the  metacarpus,  the 
two  phalanges  of  the  thumb,  the  three  phalanges  of  each  of 
the  other  fingers,  and  five  sesamoid  bones. 

The  coxal  bone,  the  femur,  the  tibia  and  patella,  the  fibula, 
the  seven  bones  of  the  tarsus,  the  five  bones  of  the  metatarsus, 
the  two  bones  of  the  great  toe,  the  three  bones  of  each  of  the 
other  toes,  and  three  sesamoid  bones. 

§  572.  The  situation  of  the  bones  is  always  internal,  or  deep. 
Whether  they  form  cavities  for  the  nervous  and  vascular  cen- 
tres, or  form  the  limbs,  they  are  all  covered  by  the  muscles 
and  the  teguments;  none  of  them  being  external. 

§  573.  The  bones  vary  greatly  as  to  size,  some  being  a  fourth, 
fifth,  or  sixth  of  the  length  of  the  body,  while  others  have 
scarcely  a  diameter  of  a  few  lines.  With  reference  to  size, 
the  bones  are  divided  into  large,  middle  sized,  small,  and  ve- 
ry small,  or  ossicula. 

§  574.  The  form  of  the  bones  is  symmetrical;     Some  are 
47 


360  GENERAL  ANATOMY. 

single  and  median,  the  others  lateral  and  in  pairs.  In  the 
former,  the  lateral  halves  are  similar  to  each  other;  in  the  lat- 
ter, each  of  the  bones  is  similar  to  that  of  the  opposite  side  of 
the  body.  There  are  in  this  respect  only  very  slight  irregu- 
larities. 

The  single  bones,  which  are  all  situated  on  the  median  line, 
are  the  vertebra,  as  well  those  which  are  moveable,  as  those 
of  the  sacrum  and  coccyx;  the  sternum,  the  occipital  bone, 
the  sphenoid,  the  ethmoid,  the  frontal  bone,  the  vomer,  the 
inferior  maxillar  bone,  and  the  hyoid  bone. 

All  the  rest  are  paired  or  double,  and  are  situated  on  the 
sides  of  the  median  line,  at  a  greater  or  less  distance  from  that 
line. 

The  bones  are  divided  according  to  their  form,  and  accord- 
ing to  the  proportion  which  their  three  geometrical  dimensions 
bear  to  each  other,  into  long,  broad,  short,  and  mixed.  In  the 
first,  one  of  the  dimensions  greatly  preponderates  over  the 
other  two;  in  the  broad  bones,  the  length  and  breadth  greatly 
exceed  the  thickness;  in  the  short  bones,  the  three  dimensions 
are  nearly  equal;  and  the  mixed  bones  participate,  in  different 
parts  of  their  extent,  of  the  characters  of  the  bones  of  two  kinds. 

§  575.  The  long  bones,  ossa  longa  sen  cylindrica,  are  situ- 
ated in  the  limbs,  where  they  constitute  broken  or  jointed  co- 
lumns. The  number  of  these  bones,  in  each  fraction  of  the 
limbs,  increases,  and  their  length  diminishes,  as  we  recede 
from  the  trunk.  Each  long  bone  is  divided  into  a  body  or 
middle  part,  and  two  extremities.  The  body  or  diaphysis,  is 
cylindrical  in  some  of  them,  and  in  others  has  the  form  of  a 
triangular  prism.  It  is  generally  a  little  bent  and  twisted. 
The  extremities  are  enlarged. 

The  broad  bones,  ossa  lata,  sue  plana,  are  situated  in  the 
trunk,  where  they  constitute  walls  of  open  cavities,  and  more 
or  less  solid.  These  bones,  which  are  flattened  in  two  oppo- 
site directions,  are  curved,  and  some  of  them  twisted.  They 
are  semi-circular,  quadrilateral,  or  polygonal.  Their  edges 
are  generally  a  little  thickened. 

The  short  or  thick  bones,  ossa  crassa,  are  situated  in  the 
vertebral  column,  in  the  hand,  and  in  the  foot,  where,  by  their 
assemblage  and  multiplicity,  they  form  solid  and  moveable 


OP  THE  BONES.  361 

parts.  They  are  globular,  tetrahedral,  cuneiform,  cuboidal, 
or  polyhedral. 

The  mixed  bones,  ossa  mizta,  are  those  which  partake  of 
the  character  of  several  kinds.  They  are  numerous:  the  occi- 
pital bone,  the  sphenoid  bone,  the  temporal  bone,  the  coxal 
bone,  the  sternum.  The  ribs  participate  of  the  character  of 
the  broad  and  short  bones.  The  long  bones  themselves  re- 
semble the  thick  bones  at  their  extremities. 

§  576.  There  are  distinguished  in  the  external  conformation 
of  the  bones,  parts,  or  regions  of  their  extent. 

In  the  single  bones  there  are,  in  general,  either  an  azygous 
and  median  parts,  and  lateral  parts,  as  the  body  and  processes 
of  the  sphenoid  bone,  the  body  and  theapophysal  masses  of  the 
vertebrae,  &c.  or  lateral  parts  only,  united  in  the  median  line, 
as  the  two  halves  of  the  frontal  bone,  &c. 

Many  bones  divide  into  parts  or  regions,  determined  by 
their  mode  of  formation  or  development.  Thus,  the  hip  bone 
is  divided  into  ilium,  ischium,  and  pubis,  the  sphenoid  bone, 
the  ethmoid  bone,  the  temporal  bone,  &c.  into  several  regions 
equally  distinct  by  the  mode  of  their  development. 

In  other  bones,  the  division  into  regions  results  solely  from 
the  situation  and  uses  of  the  parts.  Thus,  the  outer  surface  of 
the  frontal  bone  is  divided  into  an  orbitar  and  nasal  region,  a 
frontal  region,  &c. 

There  are  also  admitted  in  the  bones  geometrical  regions  or 
parts  of  their  extent.  Thus,  there  are  distinguished  and  de- 
scribed in  the  long  bones,  a  body  or  central  part  and  extremi- 
ties; in  the  broad  bones,  faces,  edges,  and  angles,  &c.  but  these 
terms  are  not  strictly  applied,  for  planes  and  angles  are  very 
rare  and  imperfect  in  the  organization. 

§  577.  The  bones  present  at  their  surface  eminences  and  de- 
pressions which  are  greatly  diversified. 

The  eminences  of  the  bones  are  distinguished  into  epiphy- 
ses  and  apophyses.  The  epiphyses  have  relation  to  the  de- 
velopment, and  will  be  described  when  we  speak  of  it. 

The  apophyses  are  bony  eminences,  continuous  with  the 
substance  of  the  bones.  They  are  extremely  numerous  and 
highly  diversified.  Few  objects  in  anatomy  have,  according- 


362  GENERAL  ANATOMY. 

ly,  been  more  differently  arranged.  They  are  distinguished 
into  articular  and  non-articular.  The  former  will  be  described 
as  we  proceed. 

The  non-articular  apophyses  are  somewhat  rough.  Their 
size  and  their  very  diversified  form  allow  them  to  be  divided 
into  three  kinds.  Some,  which  are  long  and  projecting  like 
a  branch  or  a  bony  ramification,  bear  the  name  of  branches, 
processes,  and  apophyses,  properly  so  called. 

Others,  which  are  shorter  and  thicker,  bear  the  name  of 
protuberances,  tuberosities,  and  tubercles. 

The  others,  which  are  elongated,  narrow,  and  little  protrud- 
ing, bear  the  name  of  crests,  ridges,  and  lines. 

The  synonymy  of  these  different  kinds  of  eminences  is  very 
complicated  and  difficult.  They  are  generally  designated  each 
by  names  derived  from  trivial  and  rather  loose  comparisons, 
sometimes  also  by  names  derived  from  their  situation,  their 
size,  their  direction,  and  their  uses. 

Their  general  use  is  that  of  affording  insertion  to  ligaments 
and  tendons. 

§  578.  The  external  cavities  of  the  bones  are,  like  their  emi- 
nences, distinguished  into  articular  and  non-articular.  It  is 
of  the  latter  only  that  we  have  to  speak  here. 

Of  these  cavities,  some  traverse,  and  others  do  not  traverse, 
the  substance  of  the  bone.  Of  the  latter,  some  have  a  widened 
entrance,  sloped  in  all  directions.  These  are  fossae,  fossettes, 
and  digital  impressions.  The  others  have  the  bottom  wide, 
and  the  entrance  narrow,  and  are  lined  by  the  mucous  mem- 
brane, and  filled  with  air.  These  are  sinuses,  and  when  they 
are  divided  into  several  cavities,  cells,  or  cellules.  Others  are 
elongated,  narrow,  more  or  less  deep.  These  are  called  fur- 
rows, channels,  meatuses,  and  grooves.  The  cavities  of  this 
latter  kind,  when  they  exist  on  the  edge  of  bones,  bear  the 
name  of  notches  or  incisions. 

Of  the  cavities  which  traverse  the  bones  from  side  to  side, 
some  follow  the  shortest  course,  through  a  thin  bone,  and  are 
holes,  slits,  or  fissures,  others  follow  a  longer  and  variously 
contorted  course,  and  are  canals,  conduits,  &c. 

Sometimes  several  bones  unite  to  form  a  cavity,  as  the  skull 


OF  THE  BONES.  363 

and  vertebral  canal,  the  pelvis,  the  thorax,  the  nasal  fossae,  the 
orbits,  &c. ;  or  even  to  form  a  hole  or  a  conduit,  as  the  spheno- 
palatine  hole,  the  foramen  lacerum  posterius,  &c.  the  orbital, 
palatal,  and  other  conduits. 

Of  these  simple  or  compound  cavities,  some  lodge  organs, 
others  furnish  insertions,  and  others  serve  to  transmit,  or  afford 
a  passage  to  certain  parts. 

In  certain  places  of  the  bones,  there  occur  a  multitude  of 
small  eminences  and  depressions,  very  close  to  each  other. 
This  constitutes  impressions  or  inequalities  which  serve  for 
insertions. 

§  579.  The  bones  have  internal  and  closed  cavities,  which 
are  called  medullary  cavities,  because  they  contain  the  medul- 
la, or  fat  of  the  bones.(169) 

The  long  bones  have  a  large  cylindrical  medullary  cavity, 
which  occupies  their  body,  or  middle  part,  and  which,  at  its 
extremities,  communicates  with  the  areola3  of  the  spongy  sub- 
stance. This  cavity  lodges  the  medullary  system,  and  ren- 
ders the  bone  lighter  under  the  same  volume,  and  stronger 
with  the  same  weight. 

The  extremities  of  the  long  bones,  the  short  bones,  the  broad 
bones,  and  especially  their  thick  edges,  contain  areolar  cavi- 
ties, which  also  lodge  marrow. 

Lastly,  there  are  some  also  whose  substance  is  compact,  con- 
taining only  microscopic  medullary  cavities. 

§  580.  The  bones  have  also  vascular  canals  for  the  vessels  of 
the  marrow,  and  for  those  of  their  proper  substance. 

Each  long  bone  has  at  least  one  canal  of  this  kind,  which 
passes  obliquely  through  the  walls  of  the  medullary  cavity, 
penetrates  into  it  from  above  downwards  in  the  humerus,  the 
tibia  and  the  fibula,  and  from  below  upwards  in  the  femur,  the 
radius  and  the  ulna.  This  canal  gives  passage  to  the  vessels 
and  nerves  of  the  medullary  membranes. 

The  extremities  of  the  same  bone,  the  short  and  thick  bones, 
and  the  thick  edges  of  the  broad  bones,  are  furnished  with  a 
very  great  number  of  wide  canals,  which  in  like  manner  afford 
passage  to  vessels,  and  especially  to  large  veins. 

Lastly,  the  whole  surface  of  the  bone  is  riddled  with  a  mul- 


364  GENERAL  ANATOMY. 

titude  of  small  holes  or  orifices  of  canals  into  which  very  small 
vessels  penetrate. 

§  581.  The  density  of  the  osseous  tissue  is  very  great,  but 
it  is  not  the  sam,e  in  all  parts  of  the  same  bone.  With  refer- 
ence to  this  circumstance,  the  substance  of  the  bone  is  distin- 
guished into  compact  and  spongy  or  areolar.  The  first  is  cor- 
tical, or  situated  at  the  exterior  of  the  bones.  The  other  is  in- 
ternal. 

The  compact  substance  is  that  whose  density  is  such  that  no 
interstices  are  perceived  in  it  by  the  naked  eye,  although  it  is 
perforated  with  many  medullary  and  vascular  canals  visible 
to  the  microscope.  In  the  long  bones,  these  canals  are  longi- 
tudinal. They  have  frequent  lateral  communications  with  the 
great  medullary  canal,  and  the  outer  surface  of  the  bone. 
They  are  smaller  towards  that  surface  than  towards  the  other. 
Their  mean  diameter  is  the  twentieth  of  a  line. 

The  areolar,  or  spongy  substance,  is  that  which  forms  small 
cavities,  distinct!)'  visible  to  the  naked  eye.  This  substance 
presents  several  varieties,  of  which  the  principal  are  the  fol- 
lowing:— It  consists  of  filaments  more  or  less  fine,  and  of  la- 
minae of  a  like  tenuity,  in  the  extremities  of  the  long  bones, 
and  in  the  substance  of  the  short  bones;  of  reticulated  filaments 
and  laminae  at  the  internal  surface  of  the  medullary  canal  of 
the  long  bones;  and  of  strong  laminae,  forming  narrow  areolae 
in  the  broad  and  thin  bones,  especially  in  those  of  the  skull. 

The  two  substances,  or  varieties  of  the  more  or  less  dense 
tissue  of  the  bones,  are  arranged  in  a  particular  manner  in  each 
kind  of  bone. 

In  the  long  bones,  the  body  is  formed  of  compact  substance, 
and  the  inner  surface  of  the  canal  is  bristled  with  some  reticu- 
lated filaments  and  laminae.  Towards  the  extremities,  the 
compact  substance  greatly  diminishes  in  thickness,  the  areolar 
or  spongy  substance  becomes  more  and  more  abundant  and 
fine,  the  great  canal  ends  by  becoming  continuous  with  the 
spongy  substance,  with  which  the  whole  extremity  of  the 
bone  is  filled. 

In  the  broad  bones,  the  two  surfaces  are  formed  of  compact 
substance.  Wherever  the  bone  is  thin,  these  two  laminae  touch 


OF  THE  BONES.  365 

each  other.  On  the  contrary,  where  it  is  thick,  they  are  se- 
parated by  a  layer  of  spongy  substance,  proportionate  to  the 
thickness  of  the  bone.  In  the  bones  of  the  skull,  the  inner 
table,  which  is  still  denser,  but  thinner  and  more  fragile  than 
the  outer  table,  bears  the  name  of  vitreous  lamina,  and  the 
spongy  substance,  that  of  diploe. 

The  short  bones  are  formed  of  spongy  substance,  surround- 
ed by  a  layer  of  compact  substance. 

Lastly,  the  mixed  bones,  in  the  disposition  of  the  two  sub- 
stances, participate  in  the  nature  of  the  kinds  of  bones  to  which 
they  belong. 

The  two  varieties  of  tissue,  or  the  two  substances  of  which 
we  have  been  speaking,  are,  in  reality,  one  and  the  same  tis- 
sue, one  and  the  same  substance,  differently  disposed,  rarefied 
in  one  part  and  condensed  in  the  other.  A  piece  of  compact 
substance  is  exactly  the  same  thing  as  a  lamina  or  a  filament  of 
spongy  substance.  A  given  longitudinal  section  of  a  long 
bone,  contains,  to  appearance,  the  same  quantity  of  osseous 
tissue  as  another  equal  longitudinal  section  of  the  same  bone; 
but  in  the  one,  the  substance,  or  tissue,  is  condensed,  and  leaves 
a  large  canal  in  its  centre,  while  in  the  other,  the  tissue  is  ra- 
refied, and  the  canal  replaced  by  a  multitude  of  spongy  areolag. 
These  two  substances  can  be  transformed  into  each  other. 
The  essential  difference  which  they  present  is,  so  to  speak, 
foreign  to  them;  it  depends  upon  the  presence  and  the  pene- 
tration of  the  medullary  tissue,  and  upon  its  numerous  vessels 
in  the  very  substance  of  the  spongy  bone,  and  upon  its  con- 
tact on  one  of  the  faces  only  of  the  compact  bone. 

§  582.  The  texture  of  the  bones*  is  one  of  the  points  of 

*  Malpighi.  dt  Ossium  structurd  f  in  op.  posth. — D.  Gagliardi,  Anatome 
ossium  novis  inventis  illustrata.Ttlomx,  1689. — Cl.  Havers,  Ostcologia  nova,  &c. 
Lond.  1691. — Description  exacte  des  os,  comprise  en  Irois  iraiUs>  par  J.  J. 
Courtial,  J.  L.  Petit,  et  Lemery. — Delascne,  Mem.  sur  F  organisation  des  ost 
in  Mem.  de  tAcad.  Royak  des  Sciences.  Paris,  1751. — J.  F.  Reichel,  de 
Ossium  ortu  alque  structurd.  Lips.  1760. — B.  S.  Albinus,  de  Constructions 
ossiuniy  in  Jlnnot.  Jicad.  Lib.  vii.  cap.  17. — Perenoti,  Mem.  sur  la  construc- 
tion et  sur  I'accrossement  des  os.  Mem.  de  Turin,  t.  ii.  1784. — A.  Scarpa, 
de  Penitiori  osaium  structurd  commentarius.  Lip3.  1795,  and  Paris,  1804. — 


366  GENERAL  ANATOMY. 

anatomy  that  has  given  rise  to  the  greatest  number  of  writings 
and  investigations.  Malpighi,  the  first  author  who  deserves 
mention,  considers  the  tissue  of  the  bones  as  resulting  from 
laminae,  fibres,  and  filaments,  with  an  intermediate  bony  juice. 
It  is,  according  to  him,  like  a  sponge  filled  with  wax.  Gag- 
liardi  admits  laminas  or  bractea3,  and  bony  threads  of  different 
forms,  which  resemble  them.  Havers  is  pretty  much  of  Mal- 
pighi's  opinion,  and  admits  laminae  formed  of  fibres,  and  con- 
nected by  the  bony  juice.  Lasone  describes  laminae  formed 
of  ossified  fibres,  connected  with  each  other  by  oblique  fila- 
ments. Reichel,  having  examined  portions  of  bones  softened 
in  a  mineral  acid,  saw  that  they  might  be  divided  into  lami- 
nae, and  then  into  fibres,  forming  a  porous  and  tubular  whole, 
which  is  continuous  with  the  spongy  substance.  Scarpa  con- 
cludes, from  the  examination  of  healthy  and  diseased  bones, 
of  bones  entire  and  deprived  of  earthy  substances,  and  of 
bones  before  and  after  their  entire  envelopment,  that  the  osse- 
ous tissue,  even  the  compact  substance,  is  a  cellular  and  reti- 
culated tissue,  entirely  similar  to  the  spongy  substance.  Me- 
dici has  observed,  and  the  circumstance  has  long  been  known 
to  those  who  extract  gelatine  from  bones,  that  the  compact 
substance  of  the  long  bones,  deprived  of  earthy  salts  by  the 
action  of  a  weak  acid,  divides  into  several  Iamina3  or  layers, 
adhering  to  each  other  by  fibres. 

§  583.  To  examine  the  texture  of  the  bony  tissue,  it  being 
extremely  hard,  one  is  obliged  to  have  recourse  to  chemical 
processes  which,  in  decomposing  the  bone,  must  have  some 
action  upon  the  part  which  remains  subjected  to  examination. 
Be  this  as  it  may,  if  a  bone  be  immersed  for  some  days  in  a 
vegetable  acid,  or  in  a  mineral  acid  diluted  with  water,  the 
saline  substance  which  enters  in  large  proportion  into  the 

V.  Malacarne,  Jluduarlum  obs.  et  icon,  ad  osteoL  et  osteopath.  Liidwigii  et 
Scarpoe,  Patav.  1801. — Howship,  Microscop.  Observ.  on  the  Structure  of 
Bone,  in  Medico-Chir.  Trans,  vol.  vii.  Lond.  1816. — M.  Troja,  Observazioni 
es  edperimcnti  sullc  ossa,  Napoli,  1814. — Medici,  Esperienze  intorno  alia  tis- 
situra  organica  ddk  ossa,  in  opuscoli  scientifici,  t.  ii.  Bologna,  1818. — Const 
derazioni  intorno  alia  tess.  org.  ddk  ossa,  scritte  da  M.  Medici,  &c.  in  ripusta 
allc  oppos.falt.  dal  S.  D.  C.  Spcranza,  e  dal  S.  Cav.  Jl.  Scarpa,  Bologna,  1819 


OP  THE  BONES,  367 

bone,  is  removed  from  it,  and  the  bone,  retaining  its  form  and 
size,  but  having  lost  a  part  of  its  weight,  equal  to  that  of  the 
earthy  matter  abstracted,  has  become  flexible  and  tenacious 
like  the  cartilaginiform  fibrous  tissue.  In  this  state  it  is  re- 
ducible to  glue  or  gelatin  by  decoction.  In  this  state  also,  if 
it  be  softened  by  maceration  in  water,  the  compact  substance, 
which  presented  no  apparent  texture,  divides  into  laminae, 
connected  together  by  fibres.  The  laminae  themselves,  some- 
what later,  or  with  more  difficulty,  divide  into  fibres,  which, 
by  a  more  prolonged  maceration,  swell,  and  become  areolar 
and  soft,  like  the  cellular  or  mucous  tissue. 

A  long  bone,  examined  by  this  method,  divides  at  its  mid- 
dle part  into  several  layers,  of  which  the  outermost  enve- 
lops the  whole  bone,  and  of  which  the  next,  becoming  thinner 
towards  the  extremities,  are  continuous  with  the  spongy  sub- 
stance with  which  they  are  filled.  The  broad  bones  are 
formed  of  two  laminae  only,  and  the  short  bones  of  a  single 
lamina  which  envelops  them ;  this  latter,  like  the  others, 
presenting  at  its  internal  surface  filamentous  and  laminar  pro- 
longations which  constitute  the  spongy  substance. 

The  bony  fibre  differs  therefore  especially  from  the  other 
animal  fibres  in  the  great  quantity  of  earthy  substance  which 
it  contains. 

In  fact,  if  in  place  of  removing  this  earthy  substance  and 
examining  the  organic  residuum  of  which  we  have  just  spoken, 
this  latter  be  destroyed,  by  submitting  a  bone  to  the  action  of 
fire,  there  remains  a  white  substance,  preserving  the  volume, 
form,  and  a  great  part  of  the  weight  of  the  bone.  This  hard, 
but  very  fragile  substance,  is  an  earthy  salt,  which  forms  part 
of  the  bony  tissue.  The  other  tissues  leave,  after  combustion, 
a  similar  residuum  or  ashes,  but  in  much  less  proportion,  and 
not  preserving,  like  those  of  the  bones,  the  form  and  a  part  of 
the  solidity  of  the  whole. 

§  584.  The  bony  fibre  is  therefore  a  fibre  very  similar  to 
the  cellular  one,  but  differing  from  it  in  the  very  great  quan- 
tity of  earthy  substance  which  enters  into  its  composition. 
Various  ideas  have  been  formed  as  to  the  intimate  nature  of 

this  fibre.    The  opinion  most  generally  admitted  consists  in 
48 


368  GENERAL  ANATOMY. 

viewing  the  tissue  of  the  bones  as  an  areolar  organic  tissue 
like  the  others,  but  containing  earthy  substance  in  extremely 
narrow  cavities,  much  in  the  same  manner  as  water  is  inter- 
posed in  the  tissue  of  a  moist  sponge.  Others  consider  the 
bone  as  an  intimate  mixture  or  a  combination  of  gelatine  and 
phosphate  of  lime.  Mascagni  regards  it  as  formed  of  absorb- 
ent vessels  filled  with  phosphate  of  lime.  These  hypotheses 
however,  do  not  rest  upon  any  fact,  or  rather  are  in  contra- 
diction to  facts.  At  the  same  time  it  is  not  known  in  what 
exact  proportion  the  earthy  substance  exists  to  the  organic 
substance  of  the  bones. 

§  585.  Some  tissues  belong  essentially  to  the  organization  of 
the  bones:  these  are  the  periosteum,  the  marrow,  and  the 
vessels.  y>*. 

The  periosteum  is  a  very  vascular  fibrous  membrane  which 
envelops  the  bone,  as  has  already  been  seen  (522.) 

The  medullary  membrane  is  a  very  vascular  cellular  mem- 
brane, which  contains  the  marrow,  and  serves  as  an  internal 
periosteum  to  the  bones  (169 — 178.) 

The  blood-vessels  of  the  bones,  which  are  pretty  numerous, 
and  of  different  volume,  are  distinguished  into  those  which 
first  ramify  in  the  outer  periosteum,  and  then  penetrate  into 
the  small  nutritious  foramina  of  the  compact  substance;  those 
which  penetrate,  without  ramifying,  into  the  medullary  canal, 
where  they  are  distributed  to  the  membrane  of  that  name, 
and  then  penetrate  through  the  inner  surface  into  the  compact 
substance,  where  they  communicate  with  the  preceding;  and, 
lastly,  into  those  which  penetrate  through  the  large  and  nu- 
merous foramina  of  the  short  bones  and  spongy  parts  of  the 
long  and  broad  bones,  to  be  distributed  in  the  spongy  substance, 
%  and  communicate  there,  in  the  long  bones,  with  the  vessels 
of  the  two  first  orders.  Some  anatomists  have  given  the  names 
of  nutritious  vessels  of  the  first  order  to  those  of  the  medullary 
canal  of  the  long  bones ;  nutritious  vessels  of  the  second  order, 
to  those  of  the  spongy  part;  and  of  the  third  order,  to  those 
which  pass  from  the  outer  periosteum  into  the  compact  sub- 
stance. In  general,  each  of  the  nutritious  canals  contains  an 
artery  and  a  vein.  Those  of  the  second  order  contain  very 


OP  THE  BONES.  369 

large  veins,  with  very  thin  walls,  which  appear  to  consist  only 
of  the  inner  membrane.  These  veins  appear  to  have  great 
communication  with  the  medullary  cavities  of  the  spongy  sub- 
stance. 

Lymphatic  vessels  are  seen  at  the  surface  of  the  large  bones 
only. 

No  other  nerves  are  seen  in  the  bones  than  those  which  ac- 
company the  vessels  of  the  medullary  membrane. 

§  586.  The  great  hardness  of  the  bones  depends  upon  their 
chemical  composition.  Of  all  the  organized  parts,  in  fact,  as 
has  been  seen,  they  contain  the  greatest  proportion  of  earthy 
substance.  It  must  have  been  known  all  along  that  the  bones 
are  combustible,  and  that  they  leave  an  earthy  residuum.  It 
has  also  long  been  known  that  the  bones  furnish  gelatine  or 
glue  by  decoction.  It  was  Scheele  who  announced  that  the 
earthy  part  of  the  bones  is  phosphate  of  lime.  A  hundred 
parts  of  fresh  bone  are  reduced  to  about  sixty  by  calcination. 

According  to  the  analysis  of  M.  Berzelius,  human  bones, 
deprived  of  water  and  fat,  have  the  following  composition: 
animal  matter  reducible  to  gelatine  by  decoction,  32. 17;  inso- 
luble animal  substance,  1.13;  phosphate  of  lime,  51.4;  carbo- 
nate of  lime,  11.30;  fluate  of  lime,  2.0;  phosphate  of  magne- 
sia, 1.16;  soda  and  muriate  ef  soda,  1.20. 

Fourcroy  and  M.  Vauquelin,  in  their  first  trials,  did  not  find 
phosphate  of  magnesia  in  human  bones.  According  to  M. 
Hildebrandt,  there  is  none  of  that  substance  in  them.  Accord- 
ing to  Dr.  Hatchett,  there  is  sulphate  of  lime  in  them,  which, 
according  to  M.  Berzelius,  is  a  product  of  calcination.  Lastly, 
Fourcroy  and  Vauquelin  admit,  moreover,  in  the  bones,  iron, 
magnesia,  silica,  alumina  and  phosphate  of  ammonia,  but  no 
fluate. 

Besides  the  differences  of  composition  dependent  upon  age, 
individual  constitution,  and  morbid  affections,  circumstances 
which  make  the  proportion  of  the  animal  substance  and  the 
earthy  substance  vary,  all  the  bones  have  not  exactly  the  same 
composition  in  the  same  individual.  Thus  the  bones  of  the 
skull  generally  contain  a  little  more  of  earthy  substance  than 


370  GENERAL  ANATOMY. 

the  others.  The  petrous  portion  of  the  temporal  bone  is  of  all 
the  parts  that  which  contains  most.* 

§  587.  The  bones  are  of  a  yellowish  white  colour  and  opaque, 
but  it  is  especially  by  their  hardness,  their  little  flexibility,  and 
their  resistance  to  rupture  that  they  are  remarkable,  and  it  is 
by  these  properties  that  they  perform  their  part  in  the  organ- 
ism. However  little  flexibility  and  compressibility  they  pos- 
sess, they  are  elastic. 

They  also  possess  a  slow  but  real  extensibility  and  power 
of  contraction.  Thus  the  maxillar  sinus,  the  nasal  fossae,  the 
orbit,  &c.  are  gradually  enlarged  by  the  development  of  tu- 
mours in  their  interior.  These  cavities  also  return  to  their 
previous  state  when  they  are  freed  of  these  causes  of  exten- 
sion. The  alveoli  contract  and  become  effaced  after  the  loss 
of  the  teeth,  &c. 

They  possess  no  other  kind  of  contraction.  Sensibility  ex- 
ists in  them  only  in  the  morbid  state.  Their  power  of  forma- 
tion is  very  remarkable  in  these  two  respects,  that  all  the  phe- 
nomena\vhich  belong  to  it,  as  their  first  formation,  separation, 
alterations  of  texture,  &c.  take  place  in  a  very  slow  manner, 
while  the  faculties  of  reproduction  and  accidental  production 
are  greater  in  them  than  in  any  other  tissue. 

§  588.  The  formation  of  the  bones,  ossification,  or  osteoge- 
nesist  is  a  phenomenon  which  has  much  occupied  the  attention 
of  observers,  and  which  is,  in  fact,  highly  worthy  of  it. 

*  John  Davy,  in  Monro's  Outlines  of  the  Anatomy  of  the  Human  Body. 
Edinb.  1813. 

-j-  H.  Eysson.  de  Ossibus  infantis,  cui  tractatui  annexus  cst  V.  Colter,  Os- 
sium  infantis  historia,  12mo.  Groning.  1659. — Th.  Kerkring-.  Osteogenia 
foetus.  Lug-d.  Bat.  1717. — R.  Nesbitt.  The  Human  Osteogeny.  Lond. 
1736.— J.  Baster.  De  Osteogenia.  Lug-d.  Bat.  1731.— A.  Vater  et  Ulmann. 
Osteogenia.  Viteb.  1733.— Albinus.  Ann.  Jicad.  lib.  vi.  vii.— Id.  Icones  Os- 
sium  Foetus  Humani.  accedit  Osteogeniae  brevis  historia.  Lugd.  Bat.  1737. 
— Duhamel.  Mem.  de  I'Jlcad.  Roy.  des  Sc.  1739,  41,  43-46;—  Haller,  Expe- 
rimenta  de  Ossium  formations  in  op.  min.  ii. — Herissant,  Mem.  de  tJLcad. 
Roy.  des  8c.  1768. — C.  Y.  Senff.  Nonnulla  de.  incremento  ossium  embryo- 
nurn  in  primis  graviditatis  mensibus.  Hals,  1801. — J.  Fr.  Mcckel.  Lent- 
sckes  JLrcliiv.  fur  die  Physlolog.  b.  i.  ii.  4. — J.  Howship.  Expcr.  and  Observ. 


OF  THE  BONES.  371 

The  bones  experience  in  their  development,  transforma- 
tions so  much  the  more  remarkable,  that  the  different  states 
through  which  they  pass  correspond  to  similar,  but  permanent 
states,  which  are  observed  in  animals. 

After  being  fluid,  like  all  the  other  parts,  they  become,  first, 
soft,  mucous,  or  gelatiniform;  secondly,  cartilaginous,  and 
some  of  them  fibrous  and  cartilaginous;  thirdly,  osseous. 

The  bones  are  mucous,  transparent,  and  colourless,  at  a  pe- 
riod very  close  upon  conception.  They  then  grow  by  vege- 
tation, and  form  a  continuous  whole  which  is  subsequently 
divided. 

The  cartilaginous  bones,  or  temporary  cartilages,  do  not 
make  their  appearance  until  the  end  of  the  second  month  after 
conception.  This  state  can  be  perceived  only  in  the  bones  or 
the  parts  of  bones  which  harden  somewhat  late,  for  it  is  doubt- 
ful whether  those  which  ossify  at  a  very  early  period  pass 
through  the  cartilaginous  state,  a  state  which  appears  rather 
destined  to  perform  the  functions  of  bones  previously  than  to 
be  a  period  of  ossification.  y-f.Yv  ,%$$•? 

The  osseous  state  commences  successively  in  the  different 
bones,  from  about  a  month  after  conception,  in  those  which 
ossify  soonest,  to  about  ten  or  twelve  years  after  birth,  in  those 
which  are  longest  in  becoming  ossified.  There  are  even  cer- 
tain accessory  bony  points  which  do  not  begin  to  form  until 
towards  the  fifteenth  or  eighteenth  year. 

§  589.  The  order  in  which  the  bones  begin  to  appear  and  to 
harden,  has  seemed  capable  of  being  reduced  to  rules. 

Thus  the  clavicle  and  maxillae  being  very  early  in  their  de- 
velopment, the  sternum,  the  pelvis,  and  the  limbs  being  later, 
it  has  been  said  that  the  earliness  is  in  relation  to  the  import- 
ance in  the  animal  kingdom,  or  rather  in  the  class  of  vertebrate 
animals,  where  we  in  fact  see,  from  the  class  of  fishes  upwards, 
the  clavicles  and  maxilla3  developed  at  a  very  early  period, 

on  the  Formation  of  Bone,  in  Med.  Chir.  Trans,  vol.  vi.  Loncf.  1815. — A. 
Beclard.  M6m.  sur  fOstiose,  in  Nouvcau  Journ.  de  Med.  vol.  iv.  1819.— 
Serres.  Des  Lois  dc  tostcogenic,  Analyse  des  trav.  de  TAcad.  Roy.  dcs  Sc. 
1819. 


372  GENERAL  ANATOMY. 

while  the  sternum,  pelvis,  and  limbs  are  so  in  but  a  very  small 
degree. 

It  has  also  been  established  as  a  general  proposition,  that  the 
bones  which  are  first  formed  are  those  which  are  near  the  san- 
guineous and  nervous  centres,  the  ribs  and  vertebrae  being  in 
fact  developed  at  a  very  early  period. 

It  has  also  been  said,  that  the  long  bones  appear  first,  then 
the  broad  bones,  afterwards  the  short  bones;  the  clavicle,  fe- 
mur, and  tibia  appearing  from  the  commencement,  and  the 
bones  of  the  tarsus  and  carpus  at  a  much  later  period. 

Lastly,  It  has  been  thought  that  the  large  bones  ossify  first 
and  the  others  successively. 

There  are  many  exceptions  to  these  rules. 

§  590.  Ossification  commences  at  the  end  of  the  first  month 
in  the  clavicle,  and  successively  in  the  inferior  maxillar  bone, 
the  femur,  the  tibia,  the  humerus,  the  upper  maxillary  bone, 
and  the  bones  of  the  fore-arm,  in  which  it  commences  about 
the  thirty-fifth  day.  It  commences  about  the  fortieth  day  in 
the  fibula,  the  scapula,  and  the  palatal  bones,  and  the  follow- 
ing days  in  the  proral  portion  of  the  occipital  bone,  in  the 
frontal  bone,  the  arches  of  the  first  vertebrae,  the  ribs,  the  great 
wing  of  the  sphenoid  bone,  the  zygomatic  process,  the  pha- 
langes of  the  fingers,  the  bodies  of  the  middle  vertebrae,  the 
nasal  and  zygomatic  bones,  the  ilium,  the  metacarpal  bones, 
the  extreme  phalanges  of  the  fingers  and  toes,  the  condyles  of 
the  occipital  bone,  and  then  in  its  basilar  portion,  in  the 
squamous  portion  of  the  temporal  bone,  in  the  parietal  bone, 
and  in  the  vomer,  in  all  which  bones  it  commences  about  the 
middle  of  the  seventh  week.  In  the  course  of  the  same  week 
it  also  commences  in  the  orbitar  wing  of  the  sphenoid  bone, 
and  lastly  in  the  matatarsal  bones,  the  phalanges  of  the  toes 
and  the  second  phalanges  of  the  fingers.  In  the  ten  following 
days  it  commences  in  the  body  of  the  sphenoid  bone,  in  those 
of  the  first  sacral  vertebras,  and  in  the  ring  of  the  tympanum. 
About  the  middle  of  the  third  month  it  shows  itself  in  the 
costiform  appendage  of  the  seventh  vertebra,  before  the  end 
of  the  third  month,  in  the  labyrinth,  and  towards  the  end  ol 
the  same  month,  in  -the  ischium  and  inner  pterygoid  process ; 


OP  THE  BONES.  373 

towards  the  middle  of  the  fourth  month,  in  the  ossicula  tym- 
pani;  at  mid  term,  in  the  pubis,  the  calcaneum,  the  second 
phalanges  of  the  toes,  the  lateral  masses  of  the  ethmoid  bone 
and  the  turbinated  bones  of  the  nose;  a  little  later  in  the  first 
pieces  of  the  sternum;  towards  the  sixth  month,  in  the  body 
and  odontoid  process  of  the  second  vertebra,  and  in  the  lateral 
and  anterior  masses  of  the  first  pelvic  or  sacral  vertebra;  a 
little  later  still,  in  the  astragalus;  towards  the  seventh  month, 
in  the  sphenoidal  turbinated  bone;  at  a  later  period,  in  the 
median  ridge  of  the  ethmoid  bone;  towards  the  period  of  birth, 
in  the  os  cuboides,  the  first  vertebra  of  the  coccyx  and  the 
anterior  arch  of  the  atlas;  a  year  after,  in  the  coracoid  bone, 
the  os  magnum  and  os  unciforme  of  the  carpus,  and  in  the 
first  cuneiform  bone;  about  the  third  year,  in  the  patella  and 
pyramidal  bone;  about  the  fourth  year,  in  the  third  and  second 
cuneiform  bones;  about  the  fifth  year,  in  the  os  scaphoides  of 
the  tarsus,  the  trapezium  and  os  lunare;  towards  the  eighth 
year,  in  the  scaphoid  bone  of  the  carpus;  a  year  after,  in  the 
os  trapezoides,  and  lastly,  about  the  twelfth  year,  in  the  os 
pisiforme. 

§  591.  Ossification  does  not  everywhere  result  from  the 
transformation  of  cartilage  into  bone.  The  diaphysis  of  the 
long  bones  and  the  centre  of  the  broad  bones,  which  are  deve- 
loped at  a  very  early  period,  pass  immediately  from  the  .mu- 
cous to  the  osseous  state.  The  other  parts  of  the  system  are 
at  first  cartilaginous,  and  it  is  in  them  that  the  successive  phe- 
nomena of  ossification  may  be  best  observed. 

The  cartilage,  which  for  a  longer  or  shorter  period  takes 
the  place,  and  performs  the  functions  of  the  bone  of  which  it 
has  the  form  and  of  which  it  gradually  acquires  the  volume, 
is  at  first  hollowed  with  irregular  cavities,  then  with  canals 
lined  by  vascular  membranes  filled  with  a  mucilaginous  or 
viscous  fluid;  it  becomes  opaque,  its  canals  become  red,  and 
ossification  commences  towards  its  centre. 

The  first  point  of  ossification,  punctum  ossificationis,  al- 
ways appears  in  the  substance  of  the  cartilage,  and  never  at  its 
surface.  It  is  surrounded  by  red  cartilage  at  the  place  which 
is  in  contact  with  it,  opaque  and  full  of  canals  at  a  little  dis- 


374  GENERAL  ANATOMY. 

tance  from  it,  and  at  a  still  greater  distance  homogeneous  and 
without  vessels,  but  only  perforated  with  some  canals  of  blood- 
vessels which  tend  towards  the  osseous  centre.  The  osseous 
point  continually  increases  by  growth  at  its  surface,  and  also 
by  interstitial  addition  in  its  substance.  The  cartilage,  suc- 
cessively perforated  by  cavities  and  canals  lined  by  sheaths  of 
blood-vessels,  gradually  diminishes  in  proportion  as  the  bone 
increases,  and  at  length  disappears.  The  canals  of  the  carti- 
lages themselves,  which  are  very  wide  at  the  commencement 
of  ossification,  become  smaller  and  smaller,  and  at  length  dis- 
appear when  it  is  completed.  In  the  place  of  a  cartilage  more 
or  less  thick,  but  at  first  full  or  solid,  without  cavities  and 
without  distinct  vessels,  at  a  later  period  perforated  with  ca- 
nals lined  by  vascular  and  secreting  membranes,  there  is  found 
a  very  vascular  bone,  full  of  areolar  or  spongy  cavities,  in- 
vested with  membranes  and  filled  with  adipose  marrow.  The 
bone  afterwards  becomes  less  vascular  as  age  advances. 

§  592.  The  cause  of  ossification,  like  that  of  organic  forma- 
tion in  general,  is  unknown.  From  Hippocrates  and  Aristotle 
to  Scarpa,  Bichat,  and  Mascagni,  a  multitude  of  more  or  less 
ingenious  hypotheses  have  been  proposed  on  this  obscure 
subject.* 

It  has  been  said,  that  the  last  divisions  of  the  arteries  ossify, 
or  are  filled  up  with  bony  matter,  and  that  after  being  filled 
with  bony  matter,  they  burst,  and  allow  it  to  escape  around 
them.  It  has  also  been  said,  and  with  more  probability,  that 
they  form,  and  allow  to  escape  the  ossifying  matter,  whether 
by  exhalent  extremities,  or  by  lateral  porosities.  But  what 
is  this  bony  matter?  Is  it  earthy  substance?  Where  do  the  ar- 
teries pour  forth  this  substance?  Is  it  in  the  interstitial  areo- 
laeof  a  cartilage,  as  has  commonly  been  said  since  the  time  of 
Herissant?  or  in  absorbent  vessels  which  are  filled  up,  as  Mas- 
cagni alleged?  These  are  so  many  mere  hypotheses.  All 
that  is  known  is  this; — that  the  vascularity  greatly  increases 
before  ossification,  and  that  it  always  precedes  that  process; 
that  the  cartilage  diminishes  and  disappears  in  proportion  as 

*  See  Scemmering,  De,  Corporis.  Hum.fabricfi,  T.  1.  DC  Ossibus. 


OP  THE  BONES.  375 

the  bone  forms  and  augments;  and  that  the  bone,  which  is 
highly  vascular  at  the  period  of  its  formation,  becomes  after- 
wards less  and  less  so.  As  to  the  state  in  which  the  bony  sub- 
stance is  deposited,  it  is  under  the  fluid  form,  and  its  successive 
hardening  depends  either  upon  the  continual  addition  of  a 
greater  proportion  of  earthy  substance,  or  upon  the  absorption 
of  the  vehicle  which  gave  it  its  fluidity.  Ossification  does  not 
depend  upon  the  deposition  of  the  earthy  substance  in  an  or- 
ganic tissue,  but  upon  the  simultaneous  formation  of  a  tissue 
containing  at  once  both  the  animal  substance  and  the  earthy 
substance. 

The  phenomena  of  ossification  are  different  in  the  different 
kinds  of  bones. 

§  593.  Ossification  takes  place  at  a  very  early  period  in  the 
long  bones,  commencing  in  them  from  one  to  two  months  af- 
ter conception,  according  to  the  bone.  Before  the  commence- 
ment of  ossification,  no  cartilages  are  observed  in  them.  It  is 
the  same  also  with  them  at  the  commencement  of  ossification; 
there  then  being  observed  only  a  mucilaginous  substance  be- 
tween the  osseous  cylinders.  These  osseous  cylinders  are  at 
first  thick  and  short,  whence  results  that  they  may  elongate 
greatly  before  growing  thick.  They  correspond  to  the  point 
at  which  the  principal  medullary  artery  is  afterwards  perceived. 
At  the  commencement  of  the  third  month,  there  are  perceiv- 
ed cartilaginous  extremities  at  the  end  of  these  elongated  bony 
cylinders.  Do  these  issue  by  vegetation  from  the  interior  of 
the  canal?  These  cartilaginous  extremities  have  the  same  con- 
formation as  the  extremities  are  to  have  at  a  later  period;  they 
ossify,  as  has  been  said,  in  treating  of  ossification  in  general. 
Most  of  them  only  ossify  at  the  centre,  and  then  form  epiphy- 
ses,  which  remain  a  greater  or  less  time  distinct  at  the  ends  of 
the  bones.  In  some  of  them  ossification  goes  on  from  the 
commencement,  by  the  extension  cf  the  body  of  the  bone,  in 
the  centre  of  their  cartilaginous  mass. 

§  594.  The  broad  bones  of  the  skull  begin  to  ossify  between 

the  sixtieth  and  seventieth  days.     The  pericranium  and  dura 

mater  are  then  very  vascular.     There  exists  between  these 

two   membranes   a   mucous  substance,  which  is  itself  very 

49 


37G  GENERAL  ANATOMY. 

vascular.  The  first  bony  points  appear  in  the  places  which 
are  most  full  of  blood-vessels,  under  the  form  of  isolated  grains, 
afterwards  disseminated  and  collected  into  net-works.  They 
then  form  a  lamina  thin  at  the  middle,  and  furnished  with  ra- 
diating bony  fibres  at  the  circumference.  The  surfaces  of  the 
bone  are  covered,  and  the  intervals  between  the  radiating 
fibres  are  filled  up,  by  a  reddish  and  very  vascular  mucilagin- 
ous substance.  The  pericranium  and  dura  mater  are  still  very 
red  and  vascular  at  that  period. 

§  595.  The  short  or  thick  bones  ossify  in  the  same  manner 
as  the  extremities  of  the  long  bones.  They  are  preceded  in 
their  formation  by  cartilages  which  have  the  form,  and  ulti- 
mately the  volume  of  the  bones  which  are  to  replace  them. 
These  cartilages  are  at  first  homogeneous  and  full,  and  after- 
wards present  the  successive  changes  already  described:  cavi- 
ties, vascular  membraneous  canals,  filled  with  viscous  fluid,  and 
bony  points  which  extend  from  the  centre  to  the  circumference. 

The  patella  and  sesamoid  bones  are  formed  in  a  tissue  which 
is  at  first  fibrous,  then  cartilaginous,  and  in  the  same  manner 
as  the  short  bones. 

The  mixed  bones,  are  intermediate  in  their  formation,  as 
they  are  in  their  external  figure,  and  internal  conformation, 
between  the  bones  of  the  two  different  classes. 

§  596.  Many  bones  are  formed  by  several  distinct  points  of 
ossification. 

Several  median  bones,  whether  broad  or  thick,  are  formed  by 
two  lateral  parts,  which  afterwards  unite  in  the  median  line.  Of 
this  kind  are  the  arches  of  the  vertebrae,  the  frontal  bone,  the 
body  of  the  sphenoid  bone,  the  squamous  portion  of  the  occi- 
pital bone,  the  inferior  maxillar  bone,  and  the  middle  pieces  of 
the  sternum.  But  in  several  of  the  median  bones  also,  ossifi- 
cation commences  at  the  middle,  and  extends  towards  the 
sides,  as  in  the  body  of  the  vertebrae,  the  basilar  portion  of 
the  occipital  bone,  the  crest  of  the  ethmoid  bone,  the  body  of 
the  hyoid  bone,  and  the  first  and  last  bones  of  the  sternum, 
whether  the  bone  is  formed  of  two  lateral  portions  at  an  earlier 
period,  at  the  period  of  its  conversion  into  cartilage,  for  exam- 
ple, or  whether  it  be  originally  single. 


OP  THE  BONES.  377 

Many  bones,  broad  as  well  as  short,  are  formed  of  several 
principal  or  original  points  of  ossification,  which  unite  more 
or  less  quickly.  Frequently  these  points  correspond  to  dis- 
tinct bones  in  other  genera  or  classes  of  animals.  Of  this  kind 
are  the  points  of  ossification  of  the  vertebrae,  the  occipital  bone, 
the  sphenoid  bone,  the  temporal  bone,  the  maxillary  bone,  the 
sternum,  the  coxal  bones,  the  sacrum,  &c.  There  even  occurs 
in  the  ruminating  animals  an  example  of  the  collateral  union 
of  two  long  bones  to  form  the  cannon  bone. 

§  597.  Lastly,  a  great  number  of  bones,  especially  of  long 
bones,  and  some  broad  and  short  bones,  have  accessory  or  se- 
condary points  of  ossification,  which  are  called  epiphyses*  on 
account  of  their  being  implanted  upon  the  body  of  the  bone, 
by  means  of  a  cartilage  which  lasts  for  a  longer  or  shorter  pe- 
riod. The  large  long  bones  of  the  thigh,  arm,  leg,  and  fore- 
arm, have  at  least  one  epiphysis  at  each  extremity. 

The  clavicle,  the  metacarpal,  metatarsal  and  phalangeal 
bones,  have  epiphyses  at  one  extremity  only. 

Of  the  broad  bones,  the  coxal  bones,  and  the  scapulae,  have 
marginal  epiphyses  analogous  to  these  terminal  epiphyses  of 
the  long  bones.  The  ribs  have  epiphyses  at  their  dorsal  extre- 
mity, and  at  their  tubercle. 

Of  the  short  bones,  the  vertebrae  are  almost  the  only  ones 
that  have  epiphyses;  they  have  them  at  the  two  faces  of  their 
body,  and  at  the  summit  of  all  their  processes  which  are  not 
articular.  Of  the  other  short  bones,  the  calcaneum  is  the  only 
one  that  has  an  epiphysis.  It  is  situated  at  its  posterior  extre- 
mity. 

The  epiphyses  begin  to  form  at  very  different  periods,  from 
about  fifteen  days  before  birth,  to  fifteen  or  eighteen  years 
after,  and  remain  for  a  longer  or  shorter  time  distinct  before 
uniting  with  the  body  of  the  bone.  The  periods  at  which  they 
unite  are  comprehended  between  the  fifteenth  and  twenty-fifth 
year.  Of  all  the  epiphyses,  the  one  which  ossifies  first,  is  that 
of  the  lower  extremity  of  the  femur,  ossification  commencing 

*  Plainer.  De  Ossium  Epiphysibus,  1736. — Ungebauer.  Epistola  dc 
Ossium  trunci  carp.  hum.  Epiphysibus  Sero  Onsets  carundemquc  Genesi.  Lips. 
1739.— Beclard,  foe,  cit. 


378  GENERAL  ANATOMY. 

in  it  previous  to  birth;  and  it  is  one  of  the  latest  in  being  united 
to  the  body  of  the  bone.  That  of  the  upper  extremity  of  the 
radius,  which  is  one  of  the  last  to  ossify,  is  perhaps,  on  the 
contrary,  the  one  which  is  soonest  in  uniting. 

§  598.  The  growth  of  the  bones  takes  place  in  an  evident 
manner,  by  the  successive  addition  of  new  bony  substance 
around  that  which  was  first  formed. 

The  growth  in  length  occurs  by  the  elongation  of  the 
body  of  the  long  bones  at  their  extremities.  For  this  purpose, 
the  ends  of  the  bony  cylinder  are  covered  with  bony  filaments 
or  villosities  immersed  in  the  not  yet  ossified  extremity,  hol- 
low and  vascular,  which  continually  elongate,  becoming  more 
and  more  slender  as  the  vessels  ramify  more,  and  as  the  ossi- 
fication slackens.  At  the  same  time,  the  cartilaginous  extre- 
mities, commencing  at  the  centre,  are  gradually  transformed 
into  bones  which  constitute  epiphyses. 

The  growth  in  breadth  takes  place,  in  the  flat  bones,  in  the 
same  manner,  whether  by  the  successive  addition  of  bony  sub- 
stance in  the  edge  of  the  bone,  as  in  the  bones  of  the  skull,  or 
by  the  osseous  formation,  under  a  marginal  epiphysis,  which 
covers  its  edge,  as  in  the  scapula  and  coxal  bone. 

The  growth  in  thickness  occurs  in  all  the  bones  in  the 
same  manner.  The  periosteum,  which  until  this  period  is  very 
vascular,  secretes  and  deposits  between  its  fibres,  at  the  sur- 
face of  the  bone,  osseous  substance,  at  first  mucous,  then  hard, 
which  being  thus  successively  added  to  the  surface,  increases 
the  thickness  of  the  bone. 

§  599. 'The  growth  of  the  prominences  of  bones  takes  place 
in  the  same  manner  as  that  of  the  long  bones  furnished  with 
epiphyses,  that  is  to  say,  between  the  body  of  the  bone  and 
the  base  of  the  eminence;  as  in  the  trochanters, &c.  In  others, 
it  is  at  the  surface  itself  that  the  growth  occurs,  precisely 
in  the  same  manner  as  the  growth  in  thickness  of  the  bones. 
Most  of  the  eminences  grow  in  this  way.  As  to  the  hollow- 
ing of  the  external  cavities  which  are  not  articular,  it  is  in 
many  places  determined  by  pressures,  which  without  really 
depressing  the  bone,  nevertheless  produce  a  depression  of  it; 


OF  THE  BONES.  379 

by  rendering  its  nutrition  less  active  than  in  the  surrounding 
parts. 

The  articular  eminences  and  cavities  are  moulded  upon  each 
other.  This  is  also  the  case  with  the  cavities  destined  to  lodge 
soft  or  fluid  parts,  and  the  medullary  cavities  of  the  bones. 
Their  existence  and  form  are  greatly  dependent  upon  those 
parts  which  they  contain.  Thus  the  conformation  of  the 
skull,  and  that  of  the  vertebral  canal  depend  greatly  upon 
that  of  the  nervous  centre  which  they  lodge.  The  lower  part 
of  the  vertebral  canal,  when  empty,  is  triangular,  just  as  the 
cotyloid  cavity  becomes  when  the  head  of  the  femur  has  been 
for  a  long  time  removed  from  it,  both  these  parts  being  formed 
of  three  bony  points. 

§  600.  Be  this  as  it  may,  the  termination  of  evident  growth, 
in  length  and  breadth,  depends  upon  the  uniting  of  the  long 
bones  with  their  terminal  epiphyses,  and  of  the  broad  bones 
with  their  marginal  epiphyses,  or  with  each  other.  The  ter- 
mination of  the  growth  in  thickness  depends  upon  the  cessa- 
tion of  the  osseous  formation  at  the  surface  of  the  bones.  This 
last  kind  of  growth  continues  somewhat  longer  than  the  first. 

The  growth  of  the  bones  nevertheless  continues  to  take 
place,  but  locally,  and  in  an  insensible  manner,  although  some- 
times in  a  manner  which  is  still  pretty  sensible. 

The  sensible  growth  depends  upon  a  kind  of  juxta-position 
at  the  extremities,  edges,  and  surfaces  of  the  bones.  The  in- 
sensible growth,  on  the  contrary,  is  interstitial,  and  depends 
upon  a  true  intus-susception.  Striking  examples  of  the  latter 
are  seen  in  some  morbid  cases  especially;  in  empyema,  spina- 
ventosa,  &c. 

§  601.  The  growth  being  terminated,  the  bones  remain  the 
seat  of  a  habitual  supply  or  nutrition.  Deposition  and  ab- 
sorption go  on  very  slowly  and  in  an  insensible  manner  in 
them  in  the  state  of  health,  and  especially  in  old  age.  But  in 
certain  cases  of  disease,  very  decided  changes  take  place  in 
the  properties  of  the  bones,  which  clearly  show  that  changes 
not  less  great  are  operated  in  their  composition. 

§  602.  The  facts  relative  to  the  growth  and  habitual  nutri- 


380  GENERAL  ANATOMY. 

lion  of  the  bones,  are  especially  proved  by  the  effects  of  mad- 
der upon  them. 

Mizauld  first,*  and  Belchiert  a  long  time  after,  were  the  first 
who  observed  that  when  madder  (Rubia  tinctorum,}  is  given 
to  animals  mixed  with  their  food,  their  bones  become  red. 
Duhamel,  Boehmer,|  Detlef,§  J.  Hunter,  ||  and  several  others 
have  made  curious  experiments  on  the  same  subject.  Ruther- 
fordll  has  explained  the  effect  of  madder  on  the  bones  alone, 
and  to  the  exclusion  of  all  the  other  parts  of  the  body,  by  a 
chemical  affinity  of  the  colouring  matter  of  madder  for  the 
earthy  substance  of  the  bones. 

Duhamel  found,  in  his  experiments,  that  the  bones  of  young 
animals  are  coloured  much  sooner  than  those  of  old  animals; 
that  the  progress  of  their  tincture  and  ossification  is  so  much 
the  more  rapid  the  more  vigorously  their  growth  goes  on; 
that  when  the  madder  is  discontinued,  the  bones  become 
white  again,  and  that  the  return  to  their  original  colour  is 
effected  by  the  superposition  of  white  layers  upon  the  red. 
This  last  fact  is  also  fully  demonstrated  by  Hunter's  experi- 
ments. Duhamel,  however,  imagined,  notwithstanding  these 
decisive  experiments,  that  the  bones  enlarge  in  thickness  by 
extension. 

As  to  the  growth  in  length,  Duhamel's  experiments  also  led 
him  to  think  that  this  growth,  which  he  compares  to  vegeta- 
tion, takes  place  by  the  extension  of  their  parts.  It  is  proba- 

*  Ant.  Misaldus.  Centitr.  MemorabiKum  seu  arcanorum  omnis  generis, 
1572. 

fPhilos.  Trans,  vol.  xxxix.  1736. 

+  Radicis  rubise  tinctorum  affedus  in  Corp.  JLnim.  Lips.  1751. — Ejusdem 
prolusio,  qua  callum  ossium  a  rubias  tinctorum  radicis  pastu  infectorum  descri- 
bit.  Ibid,  1752. 

§  Osrium  calli  generatlo  et  natura  perfrada  in  animalibus  rubise,  radiee 
pastis,  ossa  demonstrate!.  Goet.  1753. 

U  Exper.  and  observ.  on  the  growth  of  bones,  from  the  papers  of  the  late 
Mr.  Hunter,  by  Ev.  Home,  in  Trans,  of  a  Society  for  Improvement,  &c, 
vol.  ii.  Lond.  1800. 

\Bisput.  Med.  Inaugt  de  Dentium  Formaiionc  d  StrudurA,  &c.  Auct.R, 
Blake.  Edinb.  1798. 


OP  THE  BONES.  381 

bly  so  in  slow  and  insensible  growth,  but  the  rapid  elonga- 
tion which  takes  place  before  the  epiphyses  become  united, 
evidently  depends  upon  an  addition  of  bony  substance  to  the 
end  of  the  body  of  the  bone,  as  is  proved  by  the  following 
experiment  of  Hunter's.  The  tibia  is.  laid  bare  in  a  young 
hog,  and  perforated  at  the  two  extremities  of  the  ossified  body, 
the  interval  between  the  two  holes  being  carefully  measured. 
Some  months  after,  when  the  growth  has  advanced,  the  same 
distance  is  found  to  exist  between  the  two  bones,  and  all  the 
elongation  that  has  taken  place  has  been  beyond  the  hole,  at 
the  extremities  of  the  diaphysis. 

These  experiments,  which  leave  little  to  be  desired  with 
respect  to  the  growth  of  the  bones,  do  not  by  any  means  afford 
results  so  satisfactory  respecting  the  habitual  nutrition  of  the 
bones.  To  redden  the  bones  of  a  young  animal,  it  is  sufficient 
to  give  it  a  few  drams  of  madder,  during  a  period  of  some 
days,  while  the  same  substance  given  in  greater  quantity,  and 
during  weeks  or  months,  to  an  adult  animal,  hardly  imparts 
any  colouring  to  them. 

§  603.  After  the  growth  in  extent  has  ceased,  the  bones  still 
undergo  farther  changes,  the  most  remarkable  of  which  is  their 
decrease.*  The  medullary  canal  of  the  long  bones  continues 
to  increase  in  diameter  from  the  moment  of  their  formation. 
So  long  as  the  growth  in  thickness  continues,  the  walls  of  the 
canal  being  augmented  at  the  exterior,  preserve  their  thick- 
ness, and  even  increase  in  that  direction. 

Duhamel  made  a  very  curious  experiment  on  this  subject, 
although  he  drew  false  inferences  from  it.  Having  laid  bare 
and  surrounded  with  a  metallic  wire  a  long  bone  of  a  young 
animal  which  he  killed  some  time  after,  he  then  found  the 
wire  covered  over  by  the  bone  which  had  increased  in  thick- 
ness, and  the  canal,  having  acquired  the  diameter  of  the  metal- 
lic ring,  he  concluded  from  this  circumstance  that  the  bone 
had  enlarged  by  expansion,  by  the  widening  of  its  canal.  This 
is  not  the  case,  however.  The  bone  had  increased  at  its  ex- 

*  Albinus.  JLnnot.  Acad. — F.  Chaussard.  Hccherchcs  sur  I1 'organ,  des  vicil- 
lards.  Paris,  1822. 


382  GENERAL  ANATOMY. 

terior  by  addition,  and  diminished  at  the  interior  by  abstrac- 
tion, whence  resulted  the  enlargement  of  the  canal. 

In  fact,  when  the  growth  of  the  bone  in  thickness  is  accom- 
plished, the  canal  continuing  to  enlarge  by  internal  absorption, 
its  walls  become  thin  in  a  singular  degree,  insomuch  that, 
after  having  been  thicker  in  the  child  than  the  diameter  of  the 
canal,  and  in  the  adult  nearly  as  thick,  they  present  in  old  age 
but  a  very  small  fraction  of  that  diameter.  The  spongy  cavi- 
ties of  the  short  bones,  of  the  broad  bones,  and  of  the  extremi- 
ties of  the  long  bones,  generally  enlarge  in  the  same  manner, 
so  that,  by  this  diminution  of  the  substance  of  the  bones,  the 
skeleton  of  aged  persons  is  rendered  much  lighter  than  that  of 
others. 

The  broad  bones  of  the  skull  pretty  frequently  undergo  a 
diminution  in  thickness  of  another  kind  in  old  age.  It  results 
from  the  absorption  of  the  diploe,  and  the  approximation  of 
the  outer  table  to  the  inner,  so  as  to  produce  at  the  same  time 
a  great  diminution  of  thickness  and  an  external  depression. 
It  is  in  the  parietal  prominences  which  are  frequently  affected 
by  it,  that  this  wasting  generally  commences. 

Frequently  also,  in  old  age,  the  articular  surfaces  of  the 
bones  of  the  inferior  members  and  the  faces  of  the  vertebrae 
are  widened  and  flattened,  as  if  they  had  at  length  yielded  to 
pressure. 

§  604.  The  form  of  the  bones  is  not  the  only  property  that 
undergoes  changes  from  the  advance  of  age.  Their  consistence 
also  exhibits  remarkable  changes;  the  bones  of  children  are 
more  flexible  and  less  brittle  than  those  of  adults,  and  may  be 
bent  or  twisted  in  the  living  subject  without  breaking.  Those 
of  old  persons,  on  the  contrary,  are  denser,  harder,  and  more 
brittle  than  those  of  adults,  which  circumstances,  added  to 
their  having  become  thinner,  renders  fractures  very  common 
in  old  age.  There  is  also  a  sensible  difference  in  the  proportion 
of  the  earthy  substance,  it  being  greater  in  old  age  than  in  the 
adult  state. 

Thus,  after  the  growth  in  dimensions  has  terminated,  the  in- 
crease of  the  density  continues  in  the  bones,  as  in  all  the  other 
parts  of  the  body. 


OF  THE  BONES.  383 

§  605.  Accidental  ossification*  is  of  very  frequent  occur- 
rence, and  was  known  at  a  very  early  period.  This  ossifica- 
tion is  rarely  perfect,  and  may  in  this  respect  be  distinguished 
into  several  varieties. 

The  least  perfect  kind  of  accidental  ossification  is  called 
earthy.  It  produces  a  white,  opaque,  chalky,  soft,  friable,  and 
even  sometimes  semi-fluid  substance.  It  is  composed  of  ani- 
mal matter,  in  small  proportion,  and  earthy  substance,  and  is 
commonly  met  with  in  cysts.  Phlebolites  are  sometimes 
of  this  kind.  It  also  occurs  in  isolated  and  formless  fragments, 
in  abscesses,  in  the  lungs,  in  the  fibrous  body  of  the  uterus,  in 
the  cellular  tissue,  and  in  the  ligaments  of  persons  affected 
with  gout,  in  the  brain,  &c.  Lastly,  it  is  frequently  met  with 
infiltrated  in  the  bronchial  glands,  the  lungs,  the  liver,  the 
kidney,  the  heart,  &c. 

The  stony  accidental  ossification  is  of  very  frequent  occur- 
rence. It  is  very  hard,  opaque,  and  contains  a  greater  pro- 
portion of  earthy  substance  than  the  bones  in  their  natural 
state.  It  is  often  met  with  under  the  form  of  a  more  or  less 
thick  incrustation  under  the  serous  membranes,  in  the  proper 
membrane  of  the  spinal  marrow,  and  especially  in  the  walls 
of  the  arteries.  It  also  occurs  under  the  form  of  cysts.  It  is 
observed  under  the  form  of  isolated  masses  in  the  fibrous  bodies 
of  the  uterus  which  have  been  ossified,  and  in  the  pineal  gland, 
where  it  constitutes  the  substance  called  acerbulus.  It  is  also 
sometimes  met  with  under  the  form  of  infiltration  of  the  pan- 
creas. What  has  been  described  under  the  name  of  petrifac- 
tion of  certain  organs,  or  of  the  foetus,  is  nothing  else  than  an 
infiltration  of  very  compact  stony  bone,  so  as  to  cause  the  ani- 
mal matter  of  the  organ  to  disappear  almost  entirely. 

The  accidental  production  sometimes  differs  still  more  from 
the  bones,  resembling  in  hardness  and  polish  the  enamel  of 
the  teeth.  This  accidental  enamel  sometimes  replaces  certain 
diarthrodial  cartilages. 

Accidental  ossification  sometimes  greatly,  or  entirely,  re- 

*  J.  Van  Heckeren.  De  osteogenesi  pr&ternaturaK.  Lugd.  Bat.  1797. — 
P.  Rayer.  Mem.  sur  F  ossification  morbidc,  in  Archives  Gtntr.  de  M?d.  t.  i, 
Paris,  1823. 

50 


384  GENERAL  ANATOMY. 

sembles  the  natural  bone,  in  its  periosteum,  its  medullary 
spongy  cavities,  its  texture,  its  semi-transparency,  and  its  che- 
mical composition;  but  this  perfect  production  is  of  rare  oc- 
currence. It  has  been  met  with  under  the  form  of  an  isolated 
body  in  the  dura  mater.  I  have  also  seen  it,  but  almost  en- 
tirely compact,  under  the  form  of  laminae,  situated  in  the  an- 
terior vertebral  ligament.  The  bony  plates  which  cover  the 
costal  cartilages  are  of  the  same  nature.  There  is  also  some- 
times observed  a  perfect,  but  compact,  ossification,  under  the 
form  of  the  hydatiferous  cyst. 

Accidental  ossification,  which  also  presents  several  varieties, 
is  often  an  effect  of  age.  Many  old  persons,  however,  are  not 
affected  with  it.  Its  causes  are  most  commonly  irritation 
and  chronic  or  latent  inflammation.  It  is  more  frequent  in 
cold  than  in  warm  countries.  It  commences  with  a  plastic 
production,  and  sometimes  passes  through  the  semi-cartilagin- 
ous or  fibrous  states,  but  at  other  times  does  not.  In  general, 
it  produces  no  inconvenience  except  by  its  bulk  or  mechanical 
effects. 

The  transformation  of  permanent  cartilages  into  bone  may 
be  regarded  as  intermediate  between  natural  and  accidental 
ossification. 

§  606.  Exostosis*  is  also  an  accidental  bony  production, 
sometimes  perfect,  and  often  stony,  and  resembling  ivory. 
The  periosteum  being  irritated  or  inflamed,  there  takes  place, 
at  its  inner  surface,  in  its  substance,  and  in  a  part  of  greater 
or  less  extent  of  its  breadth,  a  deposition  of  soft,  organizable 
matter;  it  constitutes  periostosis,  which  terminates  variously. 
In  many  cases  it  ossifies,  constituting  at  first  a  kind  of  epiphy- 
sis  or  bone,  distinct  and  separable  from  the  natural  bone,  to 
which  the  exostosis  is  at  length  firmly  attached.  Sometimes  it 
consists  of  a  very  circumscribed  nodus,  which  has  been  rapid- 
ly developed.  At  other  times  it  forms  slowly,  and  consists 
of  a  voluminous  and  foliated  mass.  Sometimes,  also,  a  whole 
limb,  or  even  a  larger  portion  of  the  skeleton  is  affected  by  it. 

Spina-ventosa,  in  place  of  always  consisting  of  a  morbid 

*  On  Exostosis,  by  M.  A.  Cooper,  in  Surgical  Essays,  Part  I.  Lond.  1818. 


OF  THE  BONES.  385 

production,  is  sometimes  formed  of  organizable  substance, 
which  after  having  distended  and  dilated  the  natural  bone, 
at  last  ossifies  more  or  less  completely  in  its  interior. 

§607.  When  a  bone  is  denuded  of  the  periosteum,*  if  the 
subject  is  young,  if  the  bone  itself  be  not  altered,  and  if  it  has 
not  remained  long  uncovered,  the  wounded  soft  parts,  if  re- 
stored to  their  natural  position,  unite  by  first  intention. 

Under  contrary  circumstances,  and  in  those  in  which  the 
inflamed  periosteum  separates  from  the  bone  by  suppuration, 
in  that  in  which  it  becomes  gangrenous,  and  when  the  peri- 
osteum suppurates  or  mortifies,  &c.  the  bone,  deprived  of  its 
nutritive  apparatus,  becomes  affected  with  necrosis  at  its  sur- 
face, and  to  a  greater  or  less  depth.  The  living  part  in  the 
vicinity  of  the  dead  portion,  becomes  inflamed,  softens,  is  at 
length  detached  from  the  part  affected  with  necrosis,  and  sup- 
purates. The  dead  portion  having  thus  become  free,  falls  off. 
The  subjacent  granulations  at  length  produce  a  cicatiix  which 
covers  the  bone,  adheres  to  it,  and  forms  a  new  periosteum. 

§  608.  After  amputation,t  matters  go  on  in  one  or  other  of 
the  two  ways  above  described. 

When  the  bone  and  its  nutritive  apparatus  have  not  been 
hurt  above  the  amputated  place,  and  especially  when  the  union 
of  the  wound  is  immediate,  the  end  of  the  bone  commonly 
unites  by  first  intention  with  the  soft  parts. 

On  the  contrary,  when  the  wound  remains  open  and  sup- 
purates, when  the  periosteum  has  been  torn  or  detached  above 
the  place  of  amputation,  or  when  the  medullary  membrane 
has  been  irritated  and  inflames,  the  end  of  the  bone  becomes 
affected  with  necrosis,  and  there  is  detached  a  slice  compre- 
hending its  whole  thickness,  and  generally  gaining  obliquely 
upon  its  outer  surface,  because  the  periosteum  is  commonly 
more  injured,  or  is  injured  higher  than  the  medullary  mem- 
brane. 

*  Tenon.  Three  Memoirs  on  Exfoliation  of  the  Bones,  in  Mem.  et  Obt. 
sur  TJLnaL  Pathol  et  la  Chir.  &c.  Paris,  1816. 

f  Van  Home.  Dissertatio  deiis,  quse  inpartibus  membri,  preesertim  osseis, 
amputations  vukieratis,  notanda  sunt.  Lugd.  Bat.  1803.— L.  L.  Brachet, 
Mtm.  de  Phys.  Path,  sur  ct  que  devient  k  fragment  de  Pos  apres  une  Amputa- 
tion, in  Sullet.de  la  Soc.  Med.  d>  Emul  de  Paris,  1822. 


386  GENERAL  ANATOMY. 

In  both  cases,  moreover,  the  end  of  the  bone  ultimately  un- 
dergoes other  changes.  In  general,  it  becomes  greatly  di- 
minished in  volume  and  weight.  The  canal,  which  is  at  first 
filled  by  the  spongy  rarefaction  of  the  compact  substance,  is 
re-established,  but  is  closed  at  the  extremity  by  a  bony  pro- 
duction placed  over  it  like  a  lid. 

§  609.  Deep  necrosis*  of  the  long  bones  presents  at  the 
same  time  interesting  phenomena  of  separation  and  osseous 
production. 

When  the  medullary  membrane  of  a  long  bone  is  destroyed 
in  a  living  animal,  by  introducing  into  its  canal  a  foreign  body 
which  tears  or  cauterizes  it,  the  whole  limb  to  which  the  bone 
belongs  swells,  becomes  painful,  and  has  its  temparature  in- 
creased. At  a  later  period  abscesses  form,  which  open  and 
remain  fistulous.  There  is  seen,  or  felt  through  the  openings, 
a  moveable  bone  in  the  midst  of  the  pus,  and  contained  in 
another  bone  which  is  hollow.  The  internal  bone,  which  be- 
comes in  time  more  and  more  loose,  sometimes  gets  engaged 
by  one  of  its  extremities  in  one  of  the  apertures  of  the  external 
bone,  and  is  even  at  length  expelled.  It  is  then  seen  to  have 
the  length  of  the  diaphysis  of  the  original  bone,  and  a  variable 
thickness,  but  which  sometimes  entirely  equals  that  of  the 
original  bone.  The  new  bone,  however,  being  freed  of  the 
foreign  body,  and  being  connected  from  the  commencement 
with  the  extremities  of  the  old  bone,  which  are  now  become 
its  own  extremities,  gradually  contracts  within  itself.  The 
suppuration  diminishes,  and  at  length  entirely  ceases,  when 
the  walls,  which  have  approached  each  other  to  such  a  degree 
as  to  touch,  are  agglutinated  together,  and  at  length  become 
entirely  confounded. 

*  Chopart  and  Robert.  De  JVecrosi  Ossium  Theses  Jlnatomico-Chir. 
Parisiis,  1766. — Troja.  De  Novorum  Ossium,  &c.  Paris,  1775.  Blumen- 
bach,  in  Richter,  Chir.  Biblioth.  B.  VI. — David.  Observ.  sur  une  Maladie 
Connue  sous  le  nom  de  necrose. — Koeler.  Experimenta  circa  regenerationem 
ossium.  Getting.  1786. — J.  P.  Weidmann.  De  Necrosi  Ossium.  Franc,  ad 
Mcen.  1793,  fol. — Russel.  Practical  Essay  on  a  Certain  Disease  of  the 
Bones  called  Necrosis.  Edinb,  1794.— A.  H.  Macdonald,  de  Necroiti  ac 
calk.  Edinb.  1799.— Macartney,  in  Crowther's  Pract.  Obs.  on  the  Diseases 
of  the  Joints.  Lond.  1808.— Charmeil,  DC  la  Regeneration  des  Os.  Metz.  1821. 


OP  THE  BONES.  387 

The  new  bone,  which  is  at  first  very  soft  and  flexible,  to 
such  a  degree  as  sometimes  to  be  bent  by  the  action  of  the 
muscles,  when  the  old  bone,  engaged  by  one  extremity  in  one 
of  the  fistulous  openings,  no  longer  forms  a  solid  support  to 
it,  ultimately  acquires  and  preserves  a  density  and  hardness 
superior  to  those  of  the  original  bones. 

The  medullary  cavities  form  in  the  new  bone  in  proportion 
as  its  tissue,  which  is  at  first  uniformly  lax,  acquires  density 
at  the  exterior. 

All  these  changes  take  place  as  if  spontaneously  in  the  hu- 
man species,  in  circumstances  and  under  the  influence  of  causes 
which  appear  to  act  upon  the  periosteum  to  produce  inflamma- 
tion in  it,  and  probably  also  upon  the  medullary  membrane, 
that  is  to  say,  upon  the  internal  nutritive  apparatus,  in  such  a 
manner  as  to  alter  its  texture  and  functions. 

The  long  bones,  in  which  necrosis  occurs  most  frequently, 
are  the  following,  being  arranged  nearly  in  the  order  of  their 
frequency:  the  tibia,  femur,  the  humerus,  the  mandibular 
bone,  the  bones  of  the  fore-arm,  the  clavicle,  the  fibula,  and 
the  bones  of  the  metatarsus  and  metacarpus. 

Two  theories  have  been  proposed  on  this  subject,  the  au- 
thors of  which  have  only  erred  in  making  them  exclusive,  for 
things  sometimes  take  place  in  the  one  way  and  sometimes  in 
the  other. 

Troja,  David,  Bichat,  and  many  others,  have  admitted  that 
the  sequestrum  is  formed  by  the  entire  body  of  the  original 
bone  rendered  more  or  less  thin  by  absorption  and  by  the  sol- 
vent action  of  the  pus,  and  that  the  new  bone  results  from  a 
new  formation,  of  which  the  external  nutritive  apparatus,  that 
is  to  say,  the  periosteum  and  its  vessels,  has  furnished  the  ma- 
terials, which  being  deposited  in  its  substance,  and  especially 
in  its  internal  surface,  have  passed  through  all  the  states  of 
fluidity  and  successive  hardening  which  the  regular  bones 
present,  excepting  that  the  bony  hardening  commences  in 
many  points  at  once. 

Experiments  made  on  living  animals  show,  that  when  the 
periosteum  is  torn  off,  it  is  reproduced  along  with  the  bone; 


388  GENERAL  ANATOMY. 

but  the  hardening  of  the  latter  is  retarded  during  the  whole  of 
the  time  necessary  for  the  reproduction  of  its  vascular  envelope. 

When  things  have  thus  occurred,  i.  e.  when  it  is  a  new  bone 
that  is  formed,  the  separated  piece  has  the  same  volume  and 
appearance  as  the  original  bone,  presenting  the  same  processes, 
impressions,  lines,  and  inequalities. 

Other  pathologists,  and  in  particular  MM.  Leville,  Riche- 
rand,  and  recently  Dr.  Knox,*  maintain  that  in  all  cases, 
the  necrosis  in  question  is  confined  to  an  internal  portion  of 
the  substance  of  the  walls  of  the  medullary  canal,  and  that  the 
new  bone  simply  results  from  the  outer  part  of  the  original 
bone  which  the  necrosis  has  not  affected,  and  which  has  only 
undergone  changes  of  volume  and  consistence. 

It  is  certainly  so  in  many  cases,  and  then  the  sequestrum 
has  a  diameter  sensibly  less  than  the  original  bone,  and  its  sur- 
face is  rough  and  uneven. 

The  extremities  of  the  long  bones  become  affected  with  ne- 
crosis, and  are  reproduced  much  less  frequently  than  their  bo- 
dy. It  is  hot  uncommon,  however,  to  observe  these  pheno- 
mena at  the  upper  extremity  of  the  humerus.  They  have  also 
been  observed  at  the  lower  extremity  of  the  bones  of  the  fore- 
arm. I  have  extracted  from  the  interior  of  a  new  bone  the 
lower  extremity  of  the  tibia,  which  had  become  affected  with 
necrosis  after  a  fracture  which  happened  two  or  three  years 
previously.  The  articular  cartilage  was  all  that  was  wanting 
at  this  extremity. 

The  broad  bones  are  also  subject  to  necrosis,  but  their  re- 
production is  rare  or  imperfect.  The  scapula,  however,  after 
being  affected  with  necrosis,  has  been  seen  to  be  replaced  by 
two  other  bones. 

Necrosis  of  the  short  bones  is  much  more  common  than  is 
supposed.  It  commonly  exists  under  the  form  of  a  seques- 
trum inclosed  at  the  centre  of  the  bone.  This  constitutes  many 
of  the  alleged  cases  of  caries  of  the  bones  of  the  tarsus,  car- 
pus, &c. 

*  Edinburgh  Medical  and  Surgical  Journal,  1822  and  1823. 


OF  THE    BONES.  389 

§  610.  The  bony  substance  of  new  formation  by  which  the 
solutions  of  continuity  in  bones  are  united,  is  named  callus.* 

When  a  long  bone  is  fractured,  besides  the  rupture  of  the 
osseous  substance,  there  takes  place  a  rupture  of  the  medullary 
membrane,  and  commonly  also  of  the  periosteum,  as  well  as  of 
the  vessels  of  these  membranes  and  of  the  bone.  There  re- 
sults from  these  vascular  and  other  divisions,  a  more  or  less 
considerable  effusion  of  blood  around  and  in  the  interval  of  the 
fragments.  If  the  latter  are  kept  in  perfect  contact,  an  agglu- 
tination is  presently  effected  between  them  and  between  the 
other  divided  parts.  There  also  supervene  a  swelling  and  dis- 
tention  of  the  soft  parts  that  have  been  divided  and  of  those 
which  surround  them,  which  become  compact  like  inflamed 
cellular  tissue.  The  marrow,  at  the  place  of  the  fracture,  es- 
pecially participates  of  this  state.  All  these  parts,  and  espe- 
cially the  agglutinating  or  organizable  substance  which  dis- 
tends them,  successively  ossify,  and  form  at  the  exterior  a  bony 
ring  of  greater  or  less  extent,  the  thicknessof  which  diminishes 
from  the  centre  or  from  the  seat  of  the  fracture  towards  the 
two  extremities,  and  at  the  interior  a  fusiform  bony  mass.  The 
bone,  however,  of  which  the  two  fractured  portions  are  thus 
brought  together,  seems  until  now  to  be  in  no  degree  affected 
by  the  changes  which  are  taking  place  around  it.  It  is  only 
from  this  period,  and  in  proportion  as  these  temporary  external 
and  internal  ossifications  diminish  and  disappear  by  absorption, 
that  the  agglutination  of  the  fragments  becomes  converted  into 
a  permanent  bony  union. 

Several  pathologists,  and  in  particular  Bonn,  Callisen,  and 
J.  Bell,  have  contented  themselves  with  observing  the  facts 
without  attempting  to  explain  them.  Numerous  hypotheses, 
however,  have  been  proposed  for  the  explanation  of  these  re- 
markable phenomena.  Boerhaave,  Haller,  and  Detlef,  his  dis- 

*  Duhamel,  Mem.  de  PJlcad.  Roy.  des  Sc.  Paris,  1741. — Boehmer,  De 
Ossium  callo,  Lips.  1748. — P.  Camper,  Observationes  circa  callum  Ossium 
Fractorum,  in  Essays  and  Observ.  Phys.  and  Liter,  vol.  iii.  Ediri.  1771. — 
Bonn,  De  Ossium  Callo,  &c.  Amstel,  1783. — Macdonald,  op.  cit. — J.  How- 
ship,  in  Med.  Chir.  Trans,  vol.  ix.  Lond.  1816. — Breschet,  Quelques  Recher- 
ches  Hist,  et  Experim.  sip  k  cal.  Paris,  1819. 


390  GENERAL  ANATOMY. 

ciple,  have  admitted  that  the  fragments  are  united  by  a  gluti- 
nous or  coagulable  matter. 

J.  Hunter,  Macdonald,  and  Howship,  have  thought  that  this 
organizable  and  agglutinating  matter  is  furnished  by  the  blood. 
It  is  well  known  that  Duhamel  and  Fougeroux  have  admit- 
ted that  the  periosteum  furnishes  a  bony  ring  which  unites  the 
fragments.  Blumenbach  has  given  the  figure  of  a  human  bone 
surrounded  by  a  ring  of  this  kind.  M.  Pelletan  taught  the 
same  thing  in  his  clinical  lectures.  Camper  had  observed  that 
there  are  an  external  callus  and  an  internal  callus.  Bichat, 
M.  Dupuytren,  M.  Cruveilher,  and  others,  have  admitted  that 
these  external  and  internal  ossifications  are  provisory. 

Many  pathologists,and  especially  Bordenave,  Bichat,  Riche- 
rand,  Scarpa,  &c.  have  maintained  that  the  union  of  divided 
bones  is  effected  by  cellular  and  vascular  granulations,  like  that 
of  the  soft  parts,  which  is  true  in  either  case  only  where  the 
division  is  external  and  suppurative,  and  not  when  it  takes 
place,  as  well  as  the  union,  without  external  wound  and  with- 
out suppuration. 

1  have  already  elsewhere*  remarked,  that  all  that  these  hy- 
potheses want,  in  order  to  be  theories  or  exact  expression  of 
facts,  is  to  be  combined,  or  not  to  be  exclusive.  This  was 
Troja's  opinion,  and  is  also  that  of  M.  Boyer,  M.  Delpech,  &c. 
In  fact,  in  the  uniting  of  a  simple  fracture,  there  take  place 
in  succession,  agglutination  of  the  fragments  by  an  organizable 
fluid,  the  materials  of  which  are  furnished  by  the  blood;  ossi- 
fication of  a  similar  substance,  infiltrated  all  round  the  frac- 
ture, both  internally  and  externally;  lastly,  vascular  and  osse- 
ous union  between  the  fragments  themselves. 

The  periosteum,  which,  when  it  exists,  appears  to  perform 
so  important  a  part  in  the  production  of  the  callus,  is  no  more 
indispensable  here  than  in  the  reproduction  after  necrosis.  It 
has  been  removed  from  the  ends  of  fractured  bones  in  birds, 
and  has  been  reproduced  at  the  same  time  that  the  callus 
formed. 
Comminuted  fracture  of  the  long  bones,  and  especially  that 

*  A.  Beclard,  Propositions  sur  quelques  Points  dc  la  Alcdecine,  Paris,  1813. 


OP  THE  BONES.  391 

% 

which  is  produced  by  fire-arms,  is  accompanied,  in  its  union, 
by  a  large  and  permanent  osseous  production.  It  is  in  this 
production  especially,  in  the  same  manner  as  in  exostosis,  as 
well  as  in  reproduction  after  necrosis,  that  a  great  mass  of  new 
osseous  matter  may  be  seen.  After  being  fluid  it  becomes  solid, 
soft,  flexible,  and  elastic,  so  that  it  might  almost  be  mistaken 
for  cartilage.  But  this  substance  contains  numerous  bony 
points;  and  if  the  observation  is  made  in  an  animal  that  has 
taken  madder,  it  is  found  to  be  of  a  rose  colour,  or  even  red, 
which  is  never  the  case  with  cartilages.  It  afterwards  becomes 
hard  like  a  common  bone,  and  even  more  so.  This  permanent 
bony  tumour  bears  the  name  of  callus. 

§611.  Wounds  of  the  bones  differ  from  fractures,  in  the 
state  of  the  solution  of  continuity  itself,  and  in  its  mode  of 
reparation,  which  is  different  from  that  described  above.  The 
bony  tissue  being  very  hard,  and  possessed  of  little  flexibility, 
a  sharp  instrument  which  cuts  it  obliquely  really  produces  a 
multitude  of  small  fractures  in  the  fragment  which  it  raises, 
just  as  happens  to  a  chip  of  dry  wood  raised  by  the  blow  of  a 
hatchet  As  to  the  subsequent  union  of  this  cut,  as  that  of  a 
fracture  with  wound,  it  commonly  does  not  take  place  until 
after  an  exfoliation,  and  by  the  formation  of  suppurating  granu- 
lations. 

§  612.  The  loss  of  substance  of  the  long  bones,  in  young  and 
healthy  subjects,  is  followed  by  a  more  or  less  extensive,  and 
sometimes  complete  reparation  or  production.  In  birds,*  the 
periosteum  may  even  be  removed,  together  with  a  large  por- 
tion of  one  of  the  bones  of  the  fore-arm,  and  these  parts  are  in 
time  reproduced  by  a  kind  of  vegetation  of  the  t\vo  ends.  In 
the  human  species,  when  the  loss  of  substance  of  a  bony  cylin- 
der is  inconsiderable,  and  the  disposition  of  the  parts  does  not 
admit  of  the  fragments  being  brought  together,  there  is  pro- 
duced, by  the  sinking  and  elongation  of  the  ends,  a  cartilagini- 
form  fibrous  substance,  which  does  not  acquire  the  hardness 
of  bone  in  its  whole  extent. 

These  more  or  Jess  advantageous  results  of  the  reproduction 

*  Charmeil.     Op.  Cit. 
.  51 


33S  GENERAL  ANATOMY. 

of  a  portion  of  bone  that  has  been  removed,  have  given  rise  to 
the  practice,  in  certain  cases,  of  cutting  out  portions  of  diseased 
bones  in  their  state  of  continuity.* 

§  613.  When  the  callus  after  having  commenced  is  subjected 
to  repeated  motions  of  flexion,  twisting,  distention,  &c.  it  re- 
mains flexible,  as  in  the  preceding  case,  or  no  union  takes  place 
at  all,  and  the  ends  of  the  bones  remain  in  contact.  This  is 
also  the  case  when  the  ends  of  bones  are  separated  by  a  slight 
layer  of  muscular  tissue. 

§  614.  The  broad  bones  have  a  stronger  power  of  reparation 
and  reproduction  than  the  long  bones.  After  the  bones  of  the 
skull  have  been  trepanned,  a  production  is  formed  which  is  sel- 
dom bony  to  the  centre.  After  the  same  operation,  if  the  se- 
parated bony  operculum  is  reapplied,  it  sometimes  unites. t 
The  phenomena  of  reproduction  are  very  imperfectly  known 
in  the  short  bones. 

§615.  The  separation  of  the  epiphysesj  takes  place,  in 
young  subjects,  from  mechanical  causes,  like  fractures,  and  the 
parts  thus  separated  unite  again  by  means  of  a  similar  callus. 
Chronic  inflammation  of  the  joints  of  the  long  bones  also  some- 
times, in  children  and  young  persons,  causes  the  separation  of 
their  epiphyses,  which  are  not  yet  united.  Both  of  these 
kinds  of  separations  are  rare.  A  case  of  false  joint,  in  conse- 
quence of  the  fracture  of  the  neck  of  the  femur,  has  lately  been 
published  as  an  example  of  separation  of  the  epiphysis  in  an 
adult. 

§616.  When  an  aneurismal  tumour  meets  with  a  bone  in 
the  course  of  its  development,  the  latter  is  gradually  destroyed 
in  the  place  which  is  in  contact  with  the  tumour,  without  any 
residuum  of  its  substance  remaining.  This  destruction  bears 
the  appellation  of  wearing  of  the  bones. 

§  617.  The  morbid  anatomy  of  the  bones§  has  already  given 

*  Roux,  De  la  Resection,  &c.  Paris,  1812.—Champion,  De  la  Resection 
des  os  dans  leur  continuity.  Paris,  1815. 

f  Merrem,  Mmadversiones,  quaedam,  &?c.     Giess.  1810. 

$  Reichel,  De  Epiphysium  ab  ossium  diaphysi  diductione.     Lips.  1769. 

§  A.  Bonn.  Descriptio  Thetauri  Ossium  Morbosorwn  Hoviani.  Amstel. 
1783. — Ed.  Sandifort,  Museum  Anat.  Acad.  Lugduno~£af.avae.  Lugd.  Bat. 


OP  THE  BONES.  393 

rise  to  numerous  works  and  engravings.  It  still,  however, 
presents,  on  some  points,  many  obscurities  to  be  cleared  up, 
which,  perhaps,  depend  more  than  is  imagined  upon  vague 
comparisons  which  have  been  made  between  the  alterations  of 
the  bones  and  those  of  the  soft  parts  in  general,  without  speci- 
fying any  tissue  in  particular.  It  is  a  point  of  anatomy  and 
pathology  which  is  highly  worthy  of  attention. 

§  6 IS.  Original  vices  of  conformation*  are  rare  in  the  long 
bones;  less  so  in  the  short  bones;  frequent  in  the  broad  bones; 
rare  in  the  bones  of  the  limbs;  more  frequent  in  those  of  the 
trunk,  especially  in  the  sternum  and  ribs;  still  more  so  in  the 
bones  of  the  head ;  and  especially  in  those  of  the  cranium ;  and 
more  so  in  those  of  the  arch  than  in  those  of  the  base. 

The  most  common  variations  are  observed  in  the  reunions 
of  the  bones,  then  in  their  figure,  then  in  the  form  of  their 
holes,  and,  lastly,  in  their  apophyses. 

Most  of  these  vices  of  conformation,  like  those  of  all  the 
parts,  appear  to  depend  upon  a  defect  of  formation.  Some  of 
them,  however,  seem  to  depend  upon  an  excess  of  formation. 
They  are  of  rare  occurrence  in  the  bones  and  in  the  parts  of 
bones  which  are  first  ossified,  and,  on  the  contrary,  more  com- 
mon in  the  parts  which  form  last. 

§  619.  The  bones  are  sometimes  consecutively  altered  so  as 
to  be  increased  or  diminished  in  size.  Besides  the  spina  ven- 
tosa  and  osteosteatoma,  already  mentioned,  and  which  are 
merely  a  dilatation  of  the  bones:  the  exostoses,  whether  ex- 
ternal or  internal,  which  are  only  the  periostosis  and  the  spina 
ventosa  ossified;  the  bones  are  also  sometimes  the  seat  of  a 
hypertrophy.  The  bone  is  then  tumefied,  and  there  is  an  in- 
terstitial deposition  which  keeps  up  or  increases  their  original 
density.  In  all  cases  there  is  an  augmentation  of  weight.  At 

1793. — c.  F^Clossius,  uber  die  Krankheiten  der  Knocken.     Tubingen,  1798. 
— J.  Howship,  in  Med.  Chir.  Transac.  vol.  viii.  and  x. 

*  Van  Doeveren,  Observ.  Osteol.  varios  naturae,  lusts  in  ossibus.  hum.  corp. 
exhibent;  in  Obs.  Acad.  Specim.  Lugd.  Bat.  1765.— Sandifort,  de  ossibus 
diverso  modo  a  solitd  conformatione  abhtdentibus,  in  Observ.  Anat.  Pathol. , 
Lib.  iii.  and  iv.  Lugd.  Bat.  1777-81.  —Rosenmuller,  de  ostium  varietatibus. 
Lips.  1804. 


394  GENERAL  ANATOMY. 

other  times  the  swelling  results  simply  from  the  rarefaction  of 
the  compact  substance.  The  bone,  which  is  less  dense,  and 
more  voluminous,  has  not  then  sensibly  increased  in  weight. 
I  have  in  my  possession  a  very  fine  specimen  of  this  kind  of 
alteration,  symmetrically  occupying  the  two  parietal  promi- 
nences in  a  skiill  of  a  young  subject:  the  bone,  which  is  greatly 
rarefied,  is  extremely  vascular.  These  two  kinds  of  tumefac- 
tion, when  they  affect  the  long  bones,  sometimes  determine 
the  contraction  or  disappearance  of  the  medullary  canal.  This 
case  has  been  described  under  the  name  of  enostosis.*  I  pre- 
sented to  the  Faculty  of  Medicine  a  skeleton  in  which  almost 
all  the  bones  present  this  alteration. 

§  620.  Atrophy  of  the  bones  gives  rise  .prematurely  to 
changes  similar  to  their  diminution  in  old  age. 

In  the  Museum  of  the  Faculty  of  Paris,  there  are  long  bones 
of  a  young  man,  in  which  the  walls  of  the  medullary  canal 
are  as  thin  as  paper.  This  canal  has  been  enlarged  by  internal 
absorption,  while  no  formation  has  taken  place  at  the  exterior. 
Phthisis,  when  very  slow,  sometimes  produces  this  alteration 
in  the  bones.  It  is  also  produced  by  long  inaction. 

§  621.  Inflammation  of  the  bones  is  very  imperfectly  known. 

The  term  caries  is  one  of  the  vaguest  words  in  pathology. 
The  obscurity  of  the  thing  has  been  increased  by  comparing 
caries  to  ulcers.  What  is  most  generally  considered  as  ca- 
ries, is  a  softening  of  the  spongy  substance  of  the  bone,  such 
that  it  can  be  cut  with  a  bistoury  without  injuring  its  edge. 
This  softening  appears  to  be  the  effect  of  an  inflammation, 
which  generally  terminates  by  suppuration, and  also  sometimes 
by  necrosis. 

Rachitis  is  another  kind  of  softening  which  appears  to  de- 
pend upon  the  diminution  of  the  earthy  substance  during  the 
period  of  growth,  whence  results  the  bending  of  the  bones 
under  the  weight  of  the  body,  and  under  the  action  of  the 
muscles.  In  fact,  if  the  bones  of  rachitic  persons  be  examined 
at  the  period  when  they  are  soft,t  it  is  found  that  the  long 

*  Lobstein,  rapport  sur  les  travaux  executes  a  famphlth.  d'anat.  de  Stras- 
bourg, 1805. 

Stanley,  in  Med,  Chir.  Trans,  vol.  vii.     Lond,  1816. 


OP  THE  ARTICULATIONS.  395 

bones  have  become  spongy  in  their  whole  thickness,  and  that 
their  tissue,  which  has  become  soft  and  red,  may  easily  be  cut 
with  the  scalpel.  On  the  other  hand,  when  the  disease  is  ter- 
minated, and  the  bones  have  resumed  their  hardness  and-in- 
flexibility,  the  compact  substance  is  found  much  thicker  on 
the  concave  side  of  the  curvature  than  on  the  opposite  side; 
and  when  the  bone  is  bent  at  an  angle,  the  place  at  which  the 
flexure  exists  is  entirely  compact,  and  the  medullary  canal  is 
obliterated  in  it. 

In  the  adult  state,  the  softening  depending  upon  the  same 
cause,  may  proceed  to  the  same  extent,  and  even  farther:  the 
bones  may  become  soft  and  pliant  (Osteomalacia,  seu  Mala- 
cost  eon};  they  may  even  acquire  all  the  softness  and  flexibili- 
ty of  flesh  (Osteosarcosis}.  At  this  extreme  degree  of  softness, 
of  which  the  woman  Supiot  presented  an  example  so  gene- 
rally known,  and  in  which  the  bones  bend  like  soft  wax,  desic- 
cation diminishes  their  weight  and  changes  their  form;  de- 
coction dissolves  them;  and  their  chemical  composition  is 
changed*  to  such  a  degree  that  they  do  not  contain  more  than 
a  few  hundredth  parts  of  earthy  substance. 

Lastly,  it  may  happen,  with,  or  without  the  preceding 
changes,  that  the  animal  substance  of  the  bones  loses  its  na- 
tural tenacity,  and  these  organs,  having  become  brittle,  break 
under  the  slightest  effort. 

§  622.  Morbid  accidental  productions  are  also  sometimes  met 
with  in  the  bony  tissue;  tubercles,  scirrhus,  and  the  encepha- 
loid  production  are  not  uncommon  in  them. 


SECTION  II. 

OP   THE   ARTICULATIONS. 

§  623.  The  Articulation,  Jlrticulas,  'Ap0pa  is  the  joining  of 
the  bones.     The  term  comprehends  the  manner  in  which  they 

*  Bostock,  in  Med.  Chir.  Trans,  vol.  iv.  Lond.  1813.— J.  Davy,  in  Monro's 
Outlines  of  Anatomy. 


396  GENERAL  ANATOMY. 

meet,  and  are  fitted  to  each  other,  and  that  in  which  they  are 
mutually  connected. 

The  long  bones  meet  and  are  joined  to  each  other  by  their 
extremities;  the  broad  bones  commonly  by  their  edges;  the 
short  bones,  by  various  points  of  their  surface.  The  articular 
parts  of  the  bones  are  most  commonly  prominences  and  de- 
pressions of  different  forms,  and  which  are  adapted  to  each 
other. 

The  means  of  union  are  cartilages,  cartilaginiform  ligaments, 
and  fibrous  ligaments.  They  are  placed,  either  between  sur- 
faces which  they  connect,  and  thus  render  continuous,  or 
around  surfaces  which  remain  in  contact. 

Articulations  have  for  their  common  use,  to  connect  the 
bones,  and  thus  form  them  into  a  united  whole,  the  skeleton. 

Of  the  articulations  some  are  moveable  and  others  not  so  in 
a  sensible  degree;  none  of  them,  strictly  speaking,  however, 
is  incapable  of  motion. 

According  to  the  form  of  the  articular  parts,  the  mode  of 
union  of  these  parts,  and  their  solidity  and  mobility  variously 
combined,  the  articulations  are  divided  into  three  genera,  and 
into  several  species  and  varieties,  which  have  been  uselessly 
multiplied;  the  synarthrosis,  or  continuous  and  immoveable 
articulation;  the  diarthrosis,  or  contiguous  and  moveable  arti- 
culation; and  the  amphiarthrosis,  or  mixed  articulation,  which 
is  continuous  like  the  first,  and  moveable  like  the  second. 

Each  articulation  has  a  proper  name,  composed  of  the  names 
of  the  bones  which  are  united  in  it. 

§624.  Synarthrosis,*  or  the  immoveable  articulation,  re- 
sults from  the  union  of  all  the  bones  of  the  skull  and  face, 
excepting  the  lower  jaw,  by  edges  more  or  less  thick,  and 
furnished  with  inequalities  which  fit  into  each  other,  often 
dovetailed,  and  always  invested  with  a  synarthrodial  cartilage 
intimately  united  to  the  two  articulated  parts.  The  perioste- 

*  Duveniey.  Lettre  contenant  plusieurs  nouvelles  observations  sur  Fosteok- 
gie.  Paris,  1689. — F.  G.  Hunauld.  Rcch.  JLnat.  sur  ks  os  du  crane  de 
Fhomme.  Acacl.  des  Sc.  1730. — E.  G.  Bose.  Program,  de  suturar.  cranii 
liumnni  fabricat.  et  usu.  Lips.  1763. — Gibson,  on  the  use  of  sutures  m  the 
skulls  of  animals,  in  Mem.  of  the  Soc.  of  Manchester,  2d  series,  vol.  i.  1805. 


OF  THE  ARTICULATIONS.  397 

urn,  in  passing  from  the  one  to  the  other  bone  over  the  inter- 
vening cartilage,  also  unites  these  three  par.ts,  to  which  it  inti- 
mately adheres.  This  kind  of  articulation,  which  is  very 
solid,  has  no  sensible  motion.  It  favours  the  growth  of  the 
broad  bones  by  their  edges.  It  is  often  obliterated  in  old  age. 
Its  disunion  requires  efforts  of  the  same  kind  and  violence  as 
those  which  fracture  the  bones. 

This  kind  of  articulation,  which  has  received  the  generic 
name  of  suture,  presents  several  varieties. 

§  625.  The  true  suture  is  that  in  which  the  edges  of  the  ar- 
ticulated bones  present  numerous  and  extensive  eminences 
and  depressions,  which  receive  each  other.  Of  this  kind  are 
the  inter-parietal,  occipito-parietal,  and  fronto-parietal  articu- 
lations. This  suture  itself  presents  some  differences.  Thus,  in 
the  first,  they  are  long  tooth-like  prolongations;  in  the  second, 
they  have  the  form  of  rounded  tails;  in  the  third,  they  resem- 
ble the  teeth  of  a  saw.  These  three  varieties  have  received 
the  names  of  dentate  suture,  sutura  dentata,  serrated  suture, 
sutura  serrata,  and  margined  suture,  sutura  limbosa. 

The  harmonic  articulation,  is  that  in  which  the  edges  of  the 
bone,  which  are  more  or  less  thick,  present  rugosities  which 
are  fitted  to  each  other;  the  suture  by  which  the  nasal  bones 
are  joined  to  each  other,  is  of  this  kind. 

The  squamous  articulation  is  that  in  which  the  edges  of  the 
bones  are  sloped  like  a  chisel,  and  fitted  to  each  other  like 
the  edges'of  a  bivalve  shell.  This  disposition,  which  is  very 
decidedly  marked  in  the  junction  of  the  parietal  and  temporal 
bones,  occurs  combined  with  the  suture  or  harmonic  articula- 
tion in  many  other  articulations  of  the  skull  and  face.  In 
many  articulations,  it  is  double  and  reciprocal,  so  that  at  one 
part,  a  bone  overlaps  the  other,  which  in  another  part  overlaps 
the  first  in  its  turn.  Of  this  kind  are  the  spheno-frontal  su- 
tures. This  mortising  is  one  of  the  most  powerful  means  of 
ensuring  the  solidity  of  the  synarthrodial  articulations. 

Schinclylesis  is  a  synarthrosis  which  results  from  the  recep- 
tion of  the  crest  or  ridge  of  a  bone  into  the  groove  of  another. 
Of  this  kind  are  the  articulations  of  the  sphenoid  and  ethmoid 


398  GENERAL  ANATOMY. 

bones  with  the  vomer,  the  lachrymal  bone  with  the  nasal  pro- 
cess of  the  maxillar  bone,  &c. 

Lastly,  Gomphosis  is  a  species  of  synarthrodial  articulation, 
entirely  different  from  the  suture,  which  results  from  the  re- 
ception of  the  roots  of  the  teeth  into  the  alveoli. 

§  626.  Jlmphiarthrosis,*  or  mixed  articulation,  partakes  of 
the  nature  of  synarthrosis  in  having  the  articular  surfaces 
united  by  means  of  an  intermediate  substance,  and  of  that  of 
diarthrosis  in  having  a  considerable  degree  of  mobility.  This 
kind  of  articulation  is  confined  to  the  body  of  the  vertebrae, 
the  pubis  and  the  upper  parts  of  the  sternum. 

The  articular  parts  of  the  bones,  are  here  flat  and  broad  sur- 
faces. The  means  of  union  are  intermediate  cartilaginiform 
ligaments,  adhering  very  firmly  to  the  two  surfaces,  and  acces- 
sary ligaments  placed  at  the  exterior  of  the  articulation.  This 
kind  of  articulation,  which  is  often  called  symphysis,  pos- 
sesses a  great  degree  of  solidity,  which  is  owing  to  the  tenacity 
of  the  ligament.  Its  mobility  is  owing  to  the  flexibility  and 
elasticity  of  the  same  substance.  The  motion  consists  of  the 
flexion  or  torsion  of  the  ligament.  This  articulation,  which  is 
very  loose  and  mobile  in  childhood,  becomes  more  and  more 
firm  in  old  age,  at  which  period  it  sometimes  ossifies.  Some- 
times the  ossification  is  external  to  it,  and  only  surrounds  it 
more  or  less  completely,  as  is  especially  observed  at  the  fore 
part  of  the  body  of  the  vertebrae.  It  may  be  accidentally  too 
loose  or  too  close.  It  is  not  susceptible  of  a  true  luxation,  but 
rather  of  a  displacement,  a  drawing  asunder,  which  'always 
supposes  the  laceration  or  destruction  of  the  intervening  carti- 
laginous ligament. 

After  certain  unconsolidated  fractures,  there  are  sometimes 
produced  articulations  of  this  kind;  that  is  to  say,  the  frag- 
ments are  united  by  the  intervention  of  a  flexible  and  tena- 
cious substance,  which  permits  them  to  move  upon  each  other. 
This  mode  of  accidental  articulations  occurs  after  fractures  of 
the  patella,  the  neck  of  the  femur,  the  olecranon,  and  also 
sometimes  after  those  of  the  body  of  the  long  bones.  Amphi- 

*  A.  Beclard.  Dictionnaire  de  Medicine,  vol.  ii. 


OP  THE  ARTICULATIONS.  399 

arthroses  also  sometimes  form  in  the  place  of  some  diarthro- 
ses,  of  which  the  synovial  membrane  has  contracted  flexible 
adhesions. 

§  627.  Diarthrosis  is  a  kind  of  articulation  in  which  the 
articular  surfaces  of  the  bones  are  in  contact,  and  move  upon 
each  other. 

This  kind  of  articulation  exists  among  all  the  bones  of  the 
limbs,  whether  between  each  other,  or  between  them  and  the 
trunk,  between  the  lower  jaw  and  the  skull,  between  the  skull 
and  vertebral  column,  between  the  articular  processes  of  the 
vertebras,  between  the  ribs  and  vertebrae,  and  between  the 
costal  cartilages  and  the  sternum. 

§  628.  The  articular  parts  of  the  bones,  in  this  kind  of  arti- 
culation, are  broad  surfaces,  whose  configuration  is  reciprocal. 
These  surfaces  are  in  general,  the  one  convex,  the  other  con- 
cave. The  convex  surfaces,  or  articular  eminences,  are  some- 
times rounded  like  a  large  segment  of  a  sphere,  in  which  case 
they  are  called  heads.  Others  are  rounded,  but  elongated  in 
one  direction,  and  contracted  in  another:  these  have  been 
named  condyles.  The  heads  and  condyles  are  sometimes  sup- 
ported by  a  narrow  part,  which  is  called  the  neck.  The  arti- 
cular depressions,  or  concave  surfaces,  bear  the  name  of 
cotyloid  cavities,  when  they  have  the  form  of  a  segment  of  a 
sphere  and  are  deep;  and  that  of  glenoid  cavities,  when  they 
are  more  superficial.  Sometimes  two  condyles  are  brought 
near  each  other  laterally,  and  leave  between  them  a  neck 
which  enters  into  the  articulation  like  themselves.  This  kind 
of  surface  is  named  a  pulley,  trochlea:  Lastly,  many  articular 
surfaces,  which  are  nearly  flat,  presenting  little  convexity  or 
concavity  in  their  configuration,  have  received  no  particular 
name,  but  are  designated,  according  to  their  extent,  under  the 
generic  names  of  articular  surfaces  or  facettes. 

All  these  surfaces  are  covered  with  diarthrodial  cartilages 
(554).  These  cartilages  are  themselves  covered  by  synovial 
membranes  (210),  and  moistened  with  synovia  (216).  There 
are,  moreover,  between  certain  of  these  surfaces,  menisci  or 
chondroid  inter-articular  cartilaginous  ligaments  (531.) 

§  629.  The  means  of  union  are  fibrous  ligaments,  (512.) 

52 


400  GENERAL  ANATOMY. 

The  muscles  which  surround  the  articulations,  although  they 
do  not  enter  essentially  into  their  composition,  contribute 
powerfully  to  their  solidity. 

§  630.  Firmness  and  mobility  are  variously  combined  in  the 
diarthrodial  articulations. 

These  articulations  possess  very  diversified  motions,  as 
sliding,  rotation,  angular  opposition  and  circumduction.  The 
sliding  motion  exists  in  all  the  diarthrodial  articulations.  The 
other  motions,  on  the  contrary,  occur  only  in  a  cerain  number 
of  them.  Rotation  is  peculiar  to  certain  articulations.  Some- 
times it  is  exercised  upon  a  single  pivot,  as  around  the  odon- 
toid process  of  the  second  vertebra.  Sometimes  there  are  4;wo, 
as  in  the  double  articulation  of  the  bones  of  the  fore-arm  with 
each  other.  Sometimes  it  is  round  an  ideal  axis  that  a  bone 
turns,  as  is  exemplified  in  the  femur.  The  motion  of  opposi- 
tion, or  angular  motion,  is  that  in  which  the  bones  form  more 
or  less  open  angles  with  each  other,  according  to  the  degree 
of  motion.  It  is  distinguished  into  opposition  limited  to  two 
motions  of  flexion  and  extension,  as  at  the  elbow,  the  knee, 
&c.;  and  into  vague  opposition,  which  may  take  place  in  four 
principal  directions,  and  in  all  the  intermediate  directions,  of 
which  examples  are  offered  by  the  arm,  the  thigh,  the  thumb, 
&c.  Circumduction,  which  exists  in  all  the  articulations  pos- 
sessing vague  opposition,  is  a  motion  by  which  the  bone  which 
moves  describes  a  cone  whose  summit  corresponds  to  the 
central  extremity  of  the  bone,  and  the  base  to  its  opposite 
extremity. 

The  firmness  of  these  articulations,  like  that  of  the  others, 
is  in  the  inverse  ratio  of  their  mobility. 

§  631.  Several  kinds  of  diarthrosis  are  distinguished,  de- 
pending upon  the  configuration  of  the  surfaces,  the  means  of 
union;  and  the  motions  of  these  articulations. 

The  close  and  planiform  diarthrosis,  articulus  adstrictus, 
the  amphiarthrosis  of  some,  the  motus  obscurusof  Columbus, 
is  that  in  which  the  surfaces  are  superficial,  the  ligaments 
strong  and  tight,  the  motions  obscure  and  confined  to  sliding, 
but  capable  of  being  performed  in  several  directions.  Of  this 
kind  are  the  articulations  of  the  articular  processes  of  the  ver- 


OF  THE  ARTICULATIONS.  401 

tebrse,  and  those  of  the  bones  of  the  carpus  and  tarsus,  whether 
with  each  other  or  with  the  metatarsus  and  metacarpus. 

JLrthrodia  differs  from  the  preceding  articulation,  in  this 
respect,  that  the  surfaces  are  less  flat,  the  ligaments  less  tight, 
and  the  motions  freer  and  more  numerous.  Of  this  kind  is  the 
temporo-maxillary  articulation. 

Enarthrosis  consists  in  the  reception  of  a  head  into  a  cavity. • 
In  this  species  the  ligament  is  capsular,  and  the  motions  greatly 
diversified.  The  articulation  of  the  femur  with  the  coxal  bone 
affords  an  example  of  it. 

These  three  first  kinds  of  diarthrosis  are  orbicular  or  vague. 
Their  motions,  which  are  more  or  less  free,  may  take  place  in 
all,  or  in  many  directions.  The  following  species,  on  the  con- 
trary, are  called  alternate,  because  the  motions  are  performed 
in  them  only  in  two  opposite  directions. 

The  rotatory  diarthrosis,  commissura  trochoides  of  Fallo- 
pius,  is  that  which  allows  only  motions  of  rotation;  of  which 
kind  are  the  articulation  of  the  atlas  with  the  second  vertebra, 
and  that  of  the  radius  with  the  ulna.  It  is  also  called  lateral 
ginglymus. 

Ginglymus^  properly  so  called,  or  the  hinge  joint,  also 
called  angular  ginglymus,  is  the  articulation  in  which  there 
are  only  two  opposite  motions,  of  which  kind  is  the  elbow 
joint.  In  this  species  of  diarthrosis,  one  of  the  bones  com- 
monly presents  a  pulley,  and  the  other  a  corresponding  sur- 
face. There  are  generally  two  lateral  ligaments.  If  the  mo- 
tion of  extension  is  not  to  go  beyond  the  line  of  direction  of 
the  bones,  these  ligaments,  in  order  to  limit  the  motion,  are 
placed  nearer  the  plane  of  flexion  than  the  opposite  plane. 

§  632.  Accidental  diarthrodial  articulations  are  produced 
under  two  different  circumstances,  after  fractures  of  which  the 
pieces  have  not  united,  and  after  luxations  which  have  not  been 
reduced.  Both  are  very  complex  productions.  The  first  kind 
may  be  called  supernumerary,  the  other  supplementary  articu- 
lations. 

*  I.  F.  Isenflamm  and  Schmidt.  De  Ginglymo.— -Erlangx,  1785. 


-402  GENERAL  ANATOMY. 

§  633.  The  supernumerary  articulations*  have  long  been 
known.  They  occur  after  fractures  in  which  the  fragments 
have  not  been  brought  together,  and  those  of  which  the  frag- 
ments have  been  frequently  moved  on  each  other.  Sometimes 
also  the  defect  of  union  depends  upon  a  constitutional  affection. 
The  ends  of  the  bones,  which  have  a  different  configuration, 
and  have  become  compact  and  closed  as  after  amputation,  are 
covered  with  a  thin  layer  of  imperfect  or  fibrous  cartilage. 
They  are  covered  and  enveloped  by  a  synovial  membrane, 
surrounded  by  a  fibrous  capsule,  generally  incomplete  and 
with  irregular  ligamentous  cords.  This  kind  of  articulation 
has  been  observed,  with  a  great  number  of  variations,  in  al- 
most all  the  long  bones  of  the  limbs,  and  several  times  in  the 
lower  jaw  and  ribs. 

§  634.  The  supplementary  articulations  have  also  been  often 
observed.  They  follow  unreduced  luxations,  and  especially 
those  of  the  femur  and  humerus.  Foville  and  Pinel  Grand- 
champ  presented  me  with  an  anatomical  preparation  which  re- 
presents an  articulation  of  this  kind  that  had  been  formed  after 
an  unreduced  luxation  of  the  bones  of  the  fore-arm  behind  the 
humerus. 

In  the  articulations  of  which  we  here  speak,  there  occurs 
a  depression  in  the  point  against  which  the  head  of  the 
luxated  bone  rests.  The  circumference  of  this  point  is 
raised  by  an  accidental  ossification.  Sometimes  even  there 
also  occurs  a  circular  fibro-cartilaginous  rim  in  it.  This  newly 
formed  cavity  is  covered  with  an  imperfect  or  fibrous  cartilage. 
The  head  of  the  luxated  bone  is  commonly  flattened.  The  in- 
terior of  the  articulation  is  lined  by  a  very  distinct  synovial 
membrane  and  moistened  by  synovia.  There  is  a  fibrous 
capsule,  formed  by  the  remains  of  the  old  capsule,  adhering 
to  the  luxated  bone,  by  the  surrounding  cellular  tissue,  and  by 
a  new  production.  The  old  cavity  contracts  and  becomes  su- 
perficial, and  the  cartilage  diminishes,  or  even  entirely  disap- 

*  J.  Salzmann.  De  JLrthul.  Analogis,  quce  fracturls  Ossium  superveniunt. 
Argentor,  1718. — Langenbech,  Uber  die  Slldung  wider  naturlicher  Geknkc 
nach  Knochcnbruchen,  in  der  Neuen  Biblfur  die  Chirurg.  Getting1. 1815. 


OF  THE  ARTICULATIONS.  403 

pears.  If  it  is  in  the  haunch,  the  cotyloid  cavity  diminishes, 
and  from  being  hemispherical  becomes  triangular;  a  fact  to  be 
added  to  those  which  show  that  the  form  of  organs  depends, 
partly  at  least,  upon  their  reciprocal  action.  It  would  appear 
that  these  changes  were  in  part  known  so  early  as  the  time  of 
Hippocrates. 

§  635.  M.  Chaussier*  has  produced,  in  dogs,  the  formation 
of  accidental  articulations  intermediate  between  the  two  kinds 
above  described.  Having  by  an  incision  made  the  head  of  the 
femur  to  come  out  of  the  cotyloid  cavity,  and  having  sawn  it 
below  the  trochanter,  he  brought  the  flesh  together,  and  left 
the  animals  to  the  care  of  nature.  On  examining  the  parts  at 
periods  more  or  less  remote,  he  found  that  the  muscles  had 
drawn  the  extremity  of  the  femur  near  a  part  of  the  ischium; 
that  the  truncated  bony  extremity  was  rounded,  and  invested 
with  a  cartilaginiform  substance;  that  the  point  of  the  ischium 
against  which  it  rested  had  also  assumed  a  cartilaginous  ap- 
pearance, and  sometimes  presented  an  articular  fossette  of 
greater  or  less  depth;  lastly,  that  the  cellular  tissue  formed 
around  this  new  articulation  a  kind  of  membranous  capsule, 
in  which  was  contained  a  serous  fluid  in  greater  or  less  quan- 
tity. 

§  636.  The  diarthrodial  articulations  may  be  altered  in  their 
solidity  and  in  their  mobility;  they  may  be  too  loose  or  too 
tight,  and  they  may  also  be  luxated  or  anchylosed. 

§  637.  Luxation  is  the  more  or  less  complete  cessation  of 
the  natural  connexion  between  the  contiguous  surfaces  of 
bones.  When  it  takes  place,  the  ligaments  are  violently 
stretched,  drawn  out,  or  even  ruptured.  The  other  articular 
and  surrounding  parts  are  more  or  less  affected  by  these  lesions. 
Motion  is  then  very  difficult.  The  most  mobile  articulations 
are  the  most  susceptible  of  it.  Thus  the  arthrodiae  and  enar- 
throses  are  those  which  present  the  greatest  number  of  exam- 
ples of  it,  and  the  close  diarthroses  those  which  present  the 
fewest.  Of  the  articulations  of  the  same  species,  those  which 
are  the  least  close,  those  whose  articular  surfaces  have  the 

*  Bulletin  des  Sciences  par  la  Soc.  Philom.    Paris,  an.  viii, 


404  GENERAL  ANATOMY. 

smallest  extent,  and  those  which  take  place  between  the  longest 
bones,  are  those  which  are  most  frequently  luxated.  Thus, 
the  shoulder-joint  furnishes  of  itself  more  examples  of  luxa- 
tions than  all  the  others  together. 

§  638.  Anchylosis,*  or  the  uniting  of  the  diarthrodial  articu- 
lations, consists,  when  it  is  complete,  of  an  intimate  union,  a 
real  continuity  between  bones  which  were  previously  in  con- 
tact. The  spongy  substance  communicates  from  the  one  bone 
to  the  other.  The  compact  plates,  the  diarthrodial  cartilages, 
the  synovial  membrane  and  the  synovia,  which  separated  the 
spongy  part  of  the  two  bones,  have  disappeared.  Immobility 
continued  for  a  great  length  of  time,  but  especially  a  certain 
degree  of  inflammation,  whether  originally  in  the  synovial 
membrane,  or  at  first  in  the  ligaments  and  the  other  surround- 
ing parts,  induce  these  changes.  Sometimes  they  commence 
by  an  agglutination  of  the  synovial  membrane,  and  the  forma- 
tion between  its  surfaces  of  cellular  tissue  or  fibrous  bridles 
which  may  become  ossified  at  a  later  period.  Sometimes  the 
articulation  being  laid  open  by  a  wound  or  the  effect  of  an 
abscess,  it  is  by  suppurative  granulations  that  the  agglutination 
is  established.  In  both  cases,  the  diarthrodial  cartilages  are 
gradually  absorbed  before  the  osseous  union  takes  place.  All 
the  diarthroses  are  susceptible  of  anchylosis,  but  the  ginglymi 
more  than  the  others. 

Anchylosis  sometimes  affects  several  articulations.  All  the 
diarthroses  and  amphiarthroses  have  even  been  seen  to  be  suc- 
cessively affected  by  it,  and  the  skeleton  has  thus  become  a 
single  inflexible  mass.  M.  Percy  has  deposited  in  the  Mu- 
seum of  the  Faculty  of  Paris  a  skeleton  which  presents  this 
general  anchylosis  of  all  the  articulations. 

§  639.  At  other  times,  the  causes  of  alteration  of  which  we 
speak  determine  the  superficial  necrosis  or  wearing  out  of  the 
articular  surfaces.  It  is  in  cases  of  this  kind  that  excision  of 
the  articular  extremities  of  the  bones  has  been  practised.!  At 

«  J.  Th.  Van  de  Wympersse.  De  Ancyksi,  &e.  Lugd.  Bat.  1783.  Idem. 
De  Jlncybseos  PathoL  et  Curat.  Lug-d.  Bat.  1783. — J.  Cloquet,  in  Diction- 
naire  de  Mcdecine,  vol.  ii. 

f  H.  Park.     Account  of  a  New  Met/tod  of  Treating  Diseases  of  the  Knee 


OP  THE  SKELETON.  405 

other  times,  the  adhesion  of  the  articulation  remains  cellular 
or  fibrous,  with  a  little  mobility.  Sometimes  the  destroyed 
cartilage  is  reproduced.  At  other  times  it  is  replaced  by  the 
transformation  of  the  subjacent  bony  plate  into  ivory  or  ena- 
mel. In  cases  of  this  kind  spontaneous  luxation  of  the  bones 
sometimes  occurs. 

1  have  seen  a  singular  displacement  of  the  hip-joint,  depend- 
ing no  doubt  upon  chronic  inflammation.  In  this  case  the 
upper  part  of  the  articular  cavity  seems  to  have  yielded  to  the 
pressure  of  the  head  of  the  femur,  after  having  been  softened. 
The  cavity,  which  has  become  oval,  is  greatly  elongated  and 
hollowed  out  at  its  upper  part,  where  it  lodges  the  head  of  the 
femur,  while  the  lower  part  of  the  same  cavity  which  lodged 
it  before  is  contracted  and  superficial.  I  have  observed  this 
change  sometimes  on  one  side  only,  and  sometimes  sym- 
metrically produced  on  both  sides  at  once. 

§  640.  All  the  diseases  of  the  diarthrodial  articulations  be- 
long to  each  or  to  several  of  the  parts  of  which  they  are  formed, 
to  their  serous  membranes,  their  cartilages,  their  ligaments, 
and  to  the  articular  parts  of  the  bones. 


SECTION  III. 

OP  THE  SKELETON. 

§  641.  The  skeleton  is  the  aggregate  of  all  the  bones  con- 
nected with  each  other  by  the  articulations.  It  is  called  na- 
tural, when  the  bones  are  kept  together  by  their  proper  liga- 
ments, and  artificial,  when  the  bones  are  united  by  substances 
foreign  to  the  organization. 

It  constitutes  a  symmetrical  whole,*  which  has  the  form  and 

and  Elbow.  London,  1783.  Moreau,  De  la  Resection  des  Os.  &c.  Paris, 
1816.  J.  Jeffray. — Cases  of  the  Excision  of  Carious  Joints,  by  H.  Park  and 
P.  F.  Moreau,  with  observations.  Glasgow,  1806. — Wachter.  Diss.  de  JLr- 
ticul.  Extirp.  Groningue,  1810. — Roux,  De  la  Resection,  &c.  Paris,  1812. 
*  Loschge.  De  Scekto  Hum.  Symmetrico,  &c.  Erlang.  1795. 


406  GENERAL  ANATOMY. 

dimensions  of  the  entire  body,  which  dimensions  it  in  a  great 
measure  determines. 

It  is  'divided  into  the  trunk  and  limbs.  The  trunk,  the  cen- 
tral and  principal  part,  and  which  is  formed  in  the  median 
line  by  the  vertebral  column,  presents  two  great  cavities.  The 
one,  which  is  superior  and  posterior,  and  is  formed  by  the 
skull  and  vertebral  canal,  lodges  the  nervous  centre;  the  other, 
which  is  anterior  and  inferior,  and  is  formed  by  the  thorax, 
lodges  the  central  organs  of  the  nutritive  functions.  Other 
cavities  (those  of  the  face),  receive  the  organs  of  sense,  &c. 
The  appendages  or  limbs  which  are  furnished  with  numerous 
articulations,  possessed  of  great  mobility,  are  especially  sub- 
servient to  motion. 

§  642.  The  uses  of  the  skeleton  are  to  form  the  solid  and 
flexible  axis  of  the  body,  furnish  protecting  envelopes  to  the 
nervous  and  vascular  centres,  and  to  the  organs  of  sense,  afford 
points  of  attachment  to  the  muscles,  and  determine  by  its  ar- 
ticulations the  extent  and  direction  of  the  motions. 

The  skeleton  performs  part  of  its  functions  through  the 
hardness  and  rigidity  of  the  bones,  and  the  solidity  of  the  ar- 
ticulations. The  rest  it  performs  through  the  mobility  of  the 
articulations. 

§  643.  In  their  motions,  the  bones  articulated  by  diarthrosis 
act  in  the  manner  of  levers. 

The  greater  part  are  levers  of  the  third  kind,  or  that  in  which 
the  power  is  interposed  between  the  fulcrum  and  weight.  The 
centre  of  motion  or  fulcrum  is  in  the  articular  extremity  of  the 
bone,  the  resistance  or  weight  at  the  other  extremity,  and  the 
muscular  power  is  applied  in  an  intermediate  point,  which  is 
commonly  very  near  the  fulcrum.  Some  of  them  are  levers 
of  the  second  kind,  or  that  in  which  the  weight  is  intermediate 
between  the  fulcrum  and  power.  Some  also  are  levers  of  the 
first  kind,  in  which  the  fulcrum  is  interposed  between  the 
weight  and  the  power. 

§  644.  As  the  bones  are  not  all  formed  at  the  same  time, 
and  do  not  all  grow  in  the  same  proportion,  the  form  and  pro- 


OF  THE    SKELETON.  407 

portions  of  the  skeleton,  and  not  merely  its  dimensions  under- 
go great  changes  through  age.* 

The  proportion  of  the  head  to  the  rest  of  the  trunk  and  to 
the  limbs  is  so  much  the  greater,  the  younger  the  subject  is, 
only  within  the  twentieth  year.  At  the  second  month  after 
conception,  it  forms  half  the  height  of  the  body,  nearly  the 
fourth  at  birth,  the  fifth  when  three  years  old,  and  the  eighth 
only  when  the  growth  is  complete.  The  face  in  like  manner 
is  so  much  the  smaller,  compared  with  the  skull;  the  pelvis, 
compared  with  the  thorax,  the  limbs  compared  with  the 
trunk,  &c.  the  younger  the  subject  is.  Many  other  differences 
of  the  same  kind  will  be  pointed  out  in  the  particular  anatomy 
of  the  bones. 

§  645.  The  skeleton  presents  pretty  distinct  differences  in 
the  two  sexes,  t  In  general  the  skeleton  of  the  female  is  smaller 
and  more  delicate  than  that  of  the  male;  the  thorax  is  shorter, 
and  altogether  smaller;  it  is  also  more  mobile;  the  pelvis 
broader;  the  lumbar  region  more  elongated,  &c.  The  diar- 
throdial  articulations  are  more  mobile, the  amphiarthrosis  more 
flexible,  &c.  All  the  regions  of  the  body,  and  almost  all  the 
bones,  present  some  particular  differences. 

§646.  The  human  races  also  present  differences  in  their 
skeleton,  the  principal  of  which  have  reference  to  the  dimen- 
sions and  form  of  the  skull,  and  its  proportion  to  the  face.J 
There  are  also  some  differences  in  the  proportions  of  the  limbs. 
In  the  negro  race,  the  upper  limbs  are  longer  in  proportion  to 
the  trunk;  the  fore-arm  and  leg  are  longer  proportionally  to 
the  arm  and  thigh. 

§  647.    Lastly,   individual   varieties   are  observed    in  the 

*  Boehmer.  op.  cit. — Cheselden,  op.  cit. — Eyson,  op.  cit. — Sue,  Sur  les 
Proportions  du  squektte  de  rhomrtle,  examint  depuis  Page  k  plus  tendre, 
jusqu'd  celui  de  vingt-cinq,  Soixante  arts  et  au-dela,-  in  Mem.  Pres.  vol.  ii. — 
F.  G.  Danz,  Grundriss  der  Zergleiderangskunde  des  ungebornen  kindes, 
Francoff,  1792.— Senff,  op.  cit. 

f  See  J.  F.  Ackermann,  De  Discrimine  Sexus  prefer  genitalla.  Mogunt, 
1788. — Compare  also  Albinus,  Tabula  sceleti  hominis,  and  Soemmering-, 
Tabula  scekti  foeminei,  Francof.  ad  Moenum,  1796. 

$  Blumenbach,  Decades  Craniorum,  i.-vi.— Soemmering,  De  Ossilus. 
53 


408  GENERAL  ANATOMY. 

skeleton,  both  with  respect  to  dimensions,  and  with  reference 
to  proportion,  configuration,  want  of  symmetry,  &c. 

The  stature  of  the  body,  which  is  determined  by  the  dimen- 
sions of  the  skeleton,  is  about  five  feet  four  inches  in  the  adult 
man,  and  about  five  feet  in  the  female;  but  this  length,  which 
varies  somewhat  in  the  different  races,  and  even  in  still  more 
restricted  varieties  of  the  human  species,  presents  considerable 
differences  in  the  individuals  of  the  same  race  or  nation.  These 
differences,  like  those  of  the  other  species  of  animals,  are  con- 
fined within  certain  limits.  Thus,  dwarfs  are  seldom  of  less 
than  half  the  mean  stature,  and  giants  are  very  seldom  more 
than  a  half  higher  than  the  ordinary  stature.  What  has  been 
said  of  giants  from  seventeen  to  twenty -five  feet  high,  must  be 
referred  to  bones  of  animals  mistaken  for  human  bones. 

The  proportions  which  the  limbs  bear  to  the  trunk  and  its 
different  parts,  or  those  of  the  limbs  to  each  other,  also  present 
numerous  individual  varieties,  determined  by  those  of  the 
bones.  This  is  also  the  case  with  the  general  configuration 
and  symmetry  of  the  body,  their  variations  being  almost  all 
determined  by  those  of  the  skeleton. 

§  648.  The  osseous  system  terminates  the  systems  which 
have  for  their  basis  the  mucous  substance  or  the  cellular  tissue 
variously  modified.  The  tissues  which  remain  to  be  described 
are,  on  the  contrary,  essentially  formed  of  globules  united  by 
the  same  substance. 


OP  THE  MUSCULAR  SYSTEM.  409 


CHAPTER  IX. 


OP  THE  MUSCULAR  SYSTEM. 

§  649.  The  muscular  system,*  systema  musculare,  com* 
prebends  all  the  organs  formed  of  long,  parallel,  soft,  irritable 
and  contractile  fibres,  which  are  of  a  reddish  colour  in  warm 
blooded  animals,  and  are  called  muscular ;  these  organs 
produce  all  the  great  motions  which  take  place  in  living 
bodies. 

The  name  of  muscle,  mus,  pvj,  from  ^tr,  to  contract,  indi- 
cates this  property;  the  muscles  are  in  fact  the  organs  of  mo- 
tion. 

§  650.  It  may  appear  astonishing,  but  it  is  nevertheless 
true,  that  the  first  anatomists,  Hippocrates  and  Aristotle,  were 
unacquainted  with  the  muscles  and  ignorant  of  their  uses. 
The  anatomists  of  the  Alexandrian  school  were  acquainted 
with  these  organs,  and  have  mentioned  some  of  them.  Galen 
had  a  pretty  accurate  knowledge  of  them;  he  represents  the 
muscle  as  formed  by  the  nerve  and  by  the  ligament  divided 
into  fibrils,  forming  a  tissue  which  he  calls  stcebe,  the  inter- 
stices of  which  are  filled  with  flesh;  he  supposes  the  muscles 
to  be  endowed  with  a  tonic  faculty,  or  contractile  force,  and 
in  a  state  of  elastic  tension,  inherent  in  their  tissue  and  inde- 
pendent of  life;  movement  would  depend,  in  that  case,  on  the 
voluntary  relaxation  of  the  antagonist  muscles. 

*  W.  G.  Muys,  Investigatio  fabricae,  quse  in  partibus  musculos  componenti- 
bus  extat.  Diss.  i. ;  de  carnis  musculosse  fibrarurfi  carntarum  strudura,  Sec. 
Lug-d.  Bat.  1741,  4to,  clij.  et  432  p. — Prochaska,  de  carne  musculari  tracta- 
tus  anat.  physioL  Vienna,  1771;  et  in  op.  min,  pars.  i. ;  Viennx,  1820. — F. 
Ribes,  flictionn.  des  Sc.  Med.  articles  muscle,,  musculaire,  et  myologie. 


410  GENERAL  ANATOMY. 

In  his  time  a  voluntary  contraction  more  prompt  and  more 
extensive  than  this  contraction  by  elasticity  was  also  admitted. 
At  the  epoch  of  the  revival  of  the  sciences,  myology  was 
still  in  the  very  imperfect  state  in  which  it  had  been  left  by 
Galen;  it  is  indebted  to  James  Dubois  (Sylvius]  for  consider- 
able advancement:  he  named  most  of  the  muscles,  which  had 
previously  taken  place  only  with  respect  to  a  very  small  num- 
ber of  them.  Vesalius,  and  the  other  anatomists  of  the  Italian 
school,  Eustachi  especially,  have  perfected  the  knowledge  of 
the  muscles,  and  have  figured  them.  The  intimate  texture  of 
the  muscles,  their  contractile  action,  the  nervous  influence  of 
this  action,  and  the  movements  which  result  therefrom,  have 
been  sedulously  studied  during  the  course  of  the  two  last  cen- 
turies, and  are  still  the  subject  of  important  labours.* 

§  651.  In  the  more  simple  animals,  the  muscular  fibre  is  not 
distinctly  perceived:  in  them  movements  are  produced  by  the 
cellular  tissue.  In  the  first  of  the  series  where  the  muscular 
fibre  appears,  it  only  moves  the  tegumentary  membranes  to 
which  it  is  annexed  or  of  which  it  forms  a  part.  In  all  those 
which  possess  a  heart,  this  fibre  is  the  principal  element  of 
this  organ.  Lastly,  in  the  vertebrate  animals,  a  few  muscles 
only  are  attached  to  the  mucous  membrane,  to  the  skin,  and  to 
the  senses,  their  dependencies;  a  great  number,  on  the  contra- 
ry, are  attached  to  the  skeleton,  in  order  to  move  it. 

§  652.  In  man  there  are  two  classes  of  muscles:  the  first, 
interior,  membraniform  and  hollow,  appertaining  to  the  mu- 
cous membrane  and  the  heart,  contracting  involuntarily,  and 
subservient  to  the  functions  of  nutrition  and  of  generation,  in 
a  word,  to  the  vegetative  functions;  the  second,  exterior, 
more  or  less  thick  and  full,  belonging  to  the  skin,  to  the  senses, 
to  the  skeleton,  and  to  the  larynx,  contracting  voluntarily  and 
subservient  to  the  animal  functions.  Both  classes  present 
characters  common  to  each  other,  which  it  is  necessary  to 
consider  generally. 

•  Messrs.  Prevost  and  Dumas  are  making  observations  on  the  intimate 
texture  of  muscles  and  on  muscular  action.  They  have  had  the  goodness  to 
communicate  to  me  the  first  results,  as  yet  unpublished. 


OP  THE  MUSCULAR  SYSTEM  IN*GENERAL.  311 

SECTION  I. 

OP  THE  MUSCULAR  SYSTEM  IN  GENERAL. 

§  653.  The  muscular  system  forms  of  itself  a  great  portion 
of  the  weight  and  volume  of  the  body. 

§  654.  However  diversified  may  be  their  form  and  situa- 
tion, the  greater  part  of  the  muscles  are  divided  into  bundles, 
and  are  all  formed  of  primitive  or  simple  fibres,  collected  into 
fasciculi. 

The  authors  who  have  treated  on  this  point  of  minute  ana- 
tomy, have  in  general  presented  it  in  a  manner  but  little  in- 
telligible: some  simply  observe,  that  the  flesh  is  composed 
of  fibres;  others,  of  fleshy  stria?;  others  again,  of  fibres  and 
fibrils;  and  lastly,  others  state  that  it  is  composed  of  fibres, 
themselves  composed  of  villi.  Muys  has  made  a  ternary  divi- 
sion. He  divides  the  muscular  flesh  into  fibres,  fibrils  and 
threads.  He  subdivides  the  fibres  into  three  orders:  large, 
mean  and  small;  the  large  being  composed  of  the  mean,  and 
the  latter  of  the  small  fibres;  the  same  with  respect  to  the 
fibrils,  the  smallest  of  which  compose  the  mean,  and  these 
compose  the  largest,  the  latter  composing  the  smallest  of  the 
fibres;  the  same  again  as  to  the  threads,  of  which  the  most 
minute  of  the  fibrils  are  composed;  according  to  this  doc- 
trine, the  muscles  would  be  the  result  of  nine  successive  de- 
grees of  composition. 

Others,  rejecting  this  analysis  as  altogether  imaginary,  ad- 
mit an  infinite  divisibility.  But  it  is  well  established,  on  the 
contrary,  that,  with  respect  to  the  muscles,  as  with  all  organic 
substance,  we  arrive  by  microscopic  inspection,  at  a  degree  of 
division  finite  and  well  determined. 

§  655.  The  muscular  bundles,  lacerti,  are  not  equally  dis- 
tinct, numerous  and  voluminous  in  all  the  muscles;  the  bundles 
composing  some  of  them,  are  so  distinct  and  large  that  they 
may  be  considered  as  so  many  particular  muscles:  such  are 
the  portions  of  the  biceps,  triceps,  the  bundles  of  the  deltoid, 
of  the  masseter,  of  the  glutaeus  magnus,  &c.;  such  are  also 


412  ^ENERAL  ANATOMY. 

the  fleshy  columns  of  the  ventricles  of  the  heart,  the  longitu- 
dinal bands  of  the  colon,  &c.  There  are,  on  the  other  hand, 
many  of  the  muscles  which  scarcely  equal  a  small  portion  of 
a  bundle  of  which  the  preceding  are  composed,  and  which  are 
not  formed  of  distinct  bundles. 

The  muscular  bundles  are  themselves  formed  of  bundles  less 
voluminous,  and  these  latter  of  others  still  more  minute,  which 
may  be  distinguished  in  almost  all  the  muscles. 

§  656.  All  the  muscles  may  moreover  be  divided  into  fasci- 
culi or  fibres  visible  to  the  eye,  fasciculse  sen  Jibrse  secunda- 
rise.  These  fasciculi,  the  ultimate  degree  of  division  percep- 
tible to  the  naked  eye,  have,  in  all  the  muscles,  nearly  the 
same  form  and  the  same  thickness.  They  may,  according  to 
the  preceding  divisions,  be  perceived  by  a  longitudinal  dis- 
section, but  still  better  by  a  traverse  section,  and  especially  in 
a  muscle  boiled  or  steeped  in  alcohol.  They  have  a  prismatic, 
pentagon  or  hexagon  form,  and  never  a  cylindrical  one;  their 
diameter  varies  a  little;  their  length,  according  to  Prochaska, 
is  equal  to  the  entire  extent  of  the  interval  between  their  two 
attachments,  even  in  the  sartorius  muscle.  Haller,  on  the 
contrary,  thought  with  Albinus,  that  the  fibres  or  the  fasciculi 
were  not  so  long  as  the  muscles,  and  that  fasciculi  of  fibres 
terminated  by  tapering  off  in  the  intervals  of  other  similar 
parts;  this  does  not  appear  to  be  the  case. 

§  657.  The  muscular  fibres,  Jibrse  musculares  primarisey 
seufila  carnia,  visible  only  by  the  aid  of  the  microscope,  are 
the  ultimate  degree  of  anatomical  analysis  of  the  muscles. 
We  are  indebted  to  Hooke,  R.  Leuwenhoeck,  Dehayde,Muys, 
De  la  Torre,  Prochaska,  Wenzell,  (Brothers,)  M.  Autenrieth, 
M.  Sprengel,  Messrs.  Ed.  Home  and  Bauer,*  and  to  Messrs. 
Prevost  and  Dumas,t  for  the  best  observations  on  this  subject. 
It  must  be  remarked,  however,  that  the  first  of  these  observers 
having  in  their  researches  only  made  use  of  lenses  which  mag- 
nified about  150  times,  were  not  enabled  to  perceive  the  pri- 

*  Croonian  Lecture,  in  Philos.  Trans,  ann.  1818. 

f  Examcn  du  sang  el  de  sm  action  dans  les  divers  Phenomenes  de  la  Jric; 
in  Annalts  de  chimie  et  de  Phys.  t.  xxii. 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  413 

mitive  fibres,  which  require,  in  order  to  be  seen,  to  be  magni- 
fied about  300  times;  their  observations  therefore  relate  only 
to  secondary  fibres. 

Hooke  observed  that  the  muscles  of  many  animals  are  com- 
posed of  an  innumerable  quantity  of  fine  threads,  the  volume 
of  which  he  estimates  at  the  hundredth  part  of  a  hair,  and 
compares  its  figure  to  that  of  a  series  of  pearls  or  beads  of 
coral.  Leuwenhoeck,  after  having  perceived  the  muscular 
fibres,  which  he  calls  primitive,  conjectured  that  they  were 
again  composed,  founding  his  idea,  though  incorrectly,  on 
the  supposition  that  spermatic  animalcules,  still  nrore  minute 
than  fibres,  must  be  provided  with  nerves  and  with  mus- 
cles; he  moreover  delineated  rough  figures  of  them;  those  of 
Dehayde,  though  coarse  also,  are  more  exact.  Muys  has 
given  descriptions  of  them  equally  long  and  exact,  he  repre- 
sents them  as  most  generally  cylindrical,  and  seldom  knotty. 
De  la  Torre  says  they  are  reddish,  which  is  not  generally 
true.  The  observations  of  Prochaska,  which  are  much  more 
exact,  prove  that  these  fibres  are  parallel  but  not  always 
straight,  and  that  in  cooked  flesh  they  are  almost  always  flexu- 
ous;  that  their  form  is  not  cylindrical,  but  flat  and  prismatic; 
that  their  substance  is  diaphanous  and  appears  to  be  solid;  their 
diameter,  with  little  variation,  appeared  to  him  to  be  seven  or 
eight  times  less  than  the  largest  diameter  of  a  red  globule  of 
blood.  This  observation,  however,  seems  to  be  inaccurate; 
he  considered  these  fibres  as  constituting  the  ultimate  degree 
of  the  division  of  the  muscles,  without  going  so  far  as  to  affirm, 
however,  that  these  are  the  elementary  fibres.  The  micro- 
scopic observation  made  by  the  brothers  Wenzell,  on  a  por- 
tion of  muscle  previously  immersed  during  eight  days  in  a 
mixture  of  alcohol  and  muriatic  acid,  discovered  to  them  that 
each  fibre  was  composed  of  round  and  minute  corpusculi.  Ac- 
cording to  M.  Autenrieth,  the  diameter  of  these  fibres  is  the 
fifth  of  that  of  the  globules  of  the  blood.  M.  Sprengel,  on  the 
contrary,  estimates  the  diameter  of  the  muscular  fibre  at  seven 
times  that  of  a  globule  of  blood,  (which  is  the  three  hundredth 
part  of  a  line)  that  is  to  say,  at  about  the  fortieth  part  of  a  line; 
he  moreover  describes  it  as  angular,  striated  and  full.  The 


414  GENERAL  ANATOMY. 

microscopic  observations  of  M.  Bauer  and  of  M.  E.  Home, 
published  with  very  beautiful  plates,  represents  the  muscular 
fibre  as  identical  with  the  particles  of  blood  divested  of  their 
colouring  matter,  and   the  central  globules   of  which  have 
united  in  filaments.     Messrs.  Prevost  and  Dumas  have  uni- 
formly obtained  the  same  result,  whatever  may  have  been  the 
animal  submitted  to  their  examination,  or  whatever  may  have 
been  the  form  and  volume  of  their  globules;  my  own  observa- 
tions accord  entirely  with  theirs.     That  the  observation  may 
be  divested  of  all  doubt,  it  ought  to  be  made  on  raw  and  un- 
prepared muscular  flesh;  in  fact,   coction  and  the  action  of 
alcohol  produce  globules  by  coagulating  the  albumen,  and  we 
may  attribute  their  presence  in  the  muscular  fibre  to  these 
causes.    These  globules  are  united  by  a  medium,  invisible  be- 
cause of  its  transparency  and  want  of  colour;  it  is  a  kind  of 
jelly  or  mucous.     If  muscular  flesh   be  macerated  in  water 
frequently  renewed,  putrefaction  changing   more  promptly 
the  means  by  which  the  globules  are  united  than  the  latter 
themselves,  and  the  renewing  of  the  water  inducing  the  pro- 
duct of  putrefaction,  isolated  globules  are  obtained  similar  to 
those  of  the  coloured  particles  of  the  blood.    The  fibres  of  all 
the  muscles  have  the  same  volume  as  well  as  form. 

§  658.  Wrinkles  or  flexuosities  are  often  perceived  on  the 
fasciculi  of  the  muscles,  particularly  when  boiled.  This  ap- 
pearance was  noticed  by  Hooke,  Leuwenhoeck,  Dehayde  and 
Haller,  was  well  delineated  by  Muys,and  engaged  the  special 
attention  of  Prochaska,  who  attributes  it  to  the  contraction  of 
the  cellular  tissue,  vessels  and  nerves,  and  to  their  crispation 
by  coction.  These  apparent  wrinkles  or  stris  have  also  been 
ascribed  to  several  other  imaginary  causes,  and  have  produced 
the  supposition  that  the  fibres  have  an  articulated,  twisted  or 
spiral  disposition.  These  wrinkles  are,  or  at  least  appear  to 
be,  nothing  more  than  flexuosities  or  undulations;  they  always 
exist  in  contracted  muscles,  whether  in  the  living,  or  in  the 
dead  subject,  or  by  the  action  of  caloric.  This  flexuosity  is 
produced  of  its  own  accord  when  the  retraction  of  a  muscle  is 
assisted,  or  when  .produced  by  cutting,  by  bringing  its  attach- 
ments towards  each  other,  or  by  pushing  them  towards  each 


OF  THE  MUSCULAR  sf  STEM  IN  GENERAL.  415 

other;  on  the  contrary,  they  disappear  when  the  muscular 
fasciculi  are  extended  in  the  dead  subject.  They  disappear 
entirely  when  the  cadaverous  stiffness  has  disappeared. 

§  659.  Some  physiologists,  deceived  by  incorrect  observa- 
tions, or  governed  by  hypothetical  views,  have  admitted  false 
or  entirely  arbitrary  opinions  as  to  the  intimate  texture  of  the 
muscular  fibre:*  thus  a  great  number  of  physiologists  and 
mechanicians  have  admitted  that  the  muscular  fibre  is  hollow, 
and  that  it  consists  of  a  series  of  ovoid  vesicles,  or  of  rhom- 
boidal  cavities,  elongated  in  a  state  of  relaxation,  but  widened 
and  globular  when  the. muscles  are  in  a  state  of  contraction. 
Several  have  considered  the  muscular  fibre  to  be  hollow  and 
continuous  to  the  nerves.  Many  others  have  considered  it  as 
hollow,  vascular  and  injectable,  either  as  being  formed  solely 
of  small  arteries  or  as  consisting  of  very  minute  vessels  inter- 
vening between  the  small  arteries  and  small  veins.  Others 
have  described  these  interior  cavities,  both  vesicles  and  ca- 
nals, as  spongy  and.cellular. .  Some  have  admitted  transversal, 
nervous  or  other  fibres,  either  intended  to  retain  the  blood  in 
the  fibre,  or  to  close  its'  dilated  canal  and  to  shorten  it  by  this 
mechanism.  Others  again  have  imagined  the  fibres  to  be  a 
spiral  canal  around  a  thread  which  is  incapable  of  extension; 
While  others  have  supposed  it  to  be  twisted  like  a  thread  of  flax 
or  hemp,  £c. 

It  may  be  objected  to  all  these  a-ssertions  that  the  muscular 
fibre,  when  examined  with  good  optical  instruments,  appears 
to  be  the  result  of  a  linear  series  of  opaque  globules,  united  by 
a  medium  more  transparent,  but  that  nothing  is  found  to  indi- 
cate that  these  globules  are  vesicles;  that  when  the  muscular 
contraction  takes  place,  wrinkles  are  perceived  to  form, 'but 
these  flexuosities  are  effaced  as  soon  as  the  muscle  is  relaxed, 
no  change  at  all,  however,  occurs  in  the  figure  of  the  globules; 
that  in  insects,  in  which  no  vessels  exist,  there  are  nevertheless 
muscular  fibres  which'  consequently  can  not  be  the  continua- 
tion of  them;  "that  injection  may  indeed  swell  the  muscles  by 
infiltrating  between  the  fibres,  but  that  it  does  not  penetrate 

*  Haller,  Ekmento'pJiysiolog.  lib.  xi,  sect,  i,  et  iii.  torn.  iv. 
54   - 


416  GENE-RAf?  ANATOMY. 

them;  that*the  supposed  transverse,  twisted, 'and  spiral  fibres 
&c.,  have  never  been  seen, 'but  only  imagined,  in  support  of 
certain  hypotheses  in  reference  to  muscular  action;  that  in 
short,  the  muscular  fibre,  differing  essentially  in'  its  organic 
character,  and  in  its  vital  phenomena,  from  the  cellular  and 
nervous  tissues,  as  well  as  that  of  the  vessels,  can  not  be  as- 
similated to  these  tissues.  M.ascagni  has  revived  and  modified 
one  of  those  opinions,  by  considering  the  primitive  cylinders 
of  the  muscles'as  formed  of  absorbent  vessels  filled  with  a  con- 
tractile glutinous  substance  in  the  living  subject,  constantly 
renewed  by  the  circulation.  Nothing,  however,  demonstrates 
this  to  be  the  case,  or  that  the  fibres  are  hollow;  it  is  much 
more  probable  that  they  are  solid.  *&  pNfetfe  . 

§  660.  The  muscles  are  enveloped  by  the  cellular  tissue 
which  forms  membranes  and  sheaths  for  them:  it  is- the  same 
with  regard  to  their  bundles  and  the  subdivisions  of  these 

O 

bundles;  only,  in  proportion  as  the  parts  enveloped  are  less 
voluminous,  the  cellular  tissue  forms  envelops  more  slender 
and  soft.  The  fasciculi  are  enveloped  and  united  together  by 
almost  imperceptible  layers  of  this  tissue;  in  fact,  the  primitive 
fibres  are  united  together  in  each  fasciculus,  by  prolongations 
of  its  envelop,  which,  by  their  tenuity  and  softness,  entirely 
elude  observation.  The  cellular  envelops  are  perceptible  either 
by  separating  the  bundles  and  the  fasciculi  from  each  other,  or 
by  cutting  the  muscle  transversely. 

Adipose*  tissue  is  likewise  found  surrounding  the  muscles  in 
the  intervals  of  their  bundles,  and  sometimes  even  between 
the  fasciculi. 

§661.  The  blood-vessels  of  the  muscles,  well  described  by 
Albinus  and  Haller,  and  delineated  by  Prochaska  and  Mas- 
cagni,  are  very  numerous,  less  so,  however,  in  the  mucous 
membrane.  Their  abundance  is  proportioned  to  the  size  of 
the  muscles;  nevertheless,  the  interior  muscles  are  more  vas-- 
cular  than  the  exterior,  and  among  the  former  some  in  particu- 
lar are  very  much  so.  The  veins,  as  in  most  of  the  parts, 
possess  a  capacity  superior  to  that  of  the  arteries.  They. all 
communicate  with  the  vessels  of  the  tegumentary  membranes, 
especially  in  the  immediate  neighbourhood  of  the  muscles: 


OF  THE  MUSCULAR ••  SYSTEM  IN  GENERAL.  417 

they  all,  after  being  first  divided'  in.  the  cellular  membrane, 
and  there  presenting  considerable  anastomoses,  penetrate  at 
various  angles  the  divers  bundles,  and  are  there  again  sub- 
divided in  order  to  penetrate  between  the  fasciculi,  and  more- 
over into  the  intervals  of  the  fibres,  always  following  the  cel- 
lular envelops,  and  continually  presenting  new  divisions  and 
new  anastomoses.  In  all  their  course,  these  vessels  accompany 
the  divisions  of  the  muscles  by  twigs  parallel  to  them,  and 
again  cross  the  direction  by  other  transverse  twigs  which -sur- 
round them.  Arrived  at  their  ultimate  point  of  division,  the 
arteries  continue  their  course  with  the  veins,  without  our  be- 
ing able  to  ascertain  how  they  contribute  to  the  texture  and  to 
the  nutrition  of  the  fleshy  fibres. 

It  is  not-to.the  blood-vessels  of  the  muscles  that  the  reddish 
colour  of  these  organs  is  owing,  for  the  interior  muscles,  which 
are  very  vascular,  are  whitish. 

Lymphatic  vessels  are  to  be  distinctly  seen  in  the  intervals 
between  the  greater  pfcrt  of  the  muscles,  and  in  the  thickness 
of  some  of  them;  as  to  the  manner  in  which  they  arise,  it  is 
unknown:  possibly  they  may  be  the  continuation -of  the  cellu- 
lar tissue  interme.dial  to  the  fibres. 

§  662.  The  nerves  of  the  muscles  are  very  voluminous;  ex- 
cepting the  skin  and  the  senses,  no  part  is  so  abundantly  pro- 
vided with  them.  In  general  they  are  proportionate  in  num- 
ber and  size  to  the  volume  of  the  muscles;  nevertheless  the  in- 
terior muscles  have  less  in  general  than  the  others,  and  among 
these  latter,  those  of  the  skeleton  less  than  those'of  the  larynx 
and  senses.  They  generally  accompany  the  bloodvessels,  and 
particularly  the  arteries,  and  are  slightly  attached  to  them  by 
the  cellular  tissue.  In  order  to  perceive  them  distinctly,  the 
muscles  must  be  mascerated  until  arrived  at  a  state  of  putre- 
faction, which  in  effect  destroys  the  muscles  more  rapidly  than 
the.  nerves;  they  penetrate  at  divers  points  into  the  muscles, 
and  there  are  divided  in  the  same  manner  as  the  vessels;  but 
they  very  soon  elude  the  sight,  without  the  possibility  of  being 
seen  by.any  artificial  means;  so  that  nothing  can  be  positively 
affirmed  as  to  their  termination.  It  is  conjectured  with  some 
appearance  of  probability,  that  .their  divisions  extend  as  far  as  ' 


418  GENERAL  ANATOMY. 

the  primitive  fibres.  It  would  seem  that  before  they  disappear 
altogether,  they  become  soft,  divesting  themselves'of  their  own 
jenvelop,  so  that  their  medullary  substance  comes  in  imme- 
diate contact  with  the  muscular  fibre.  Munro  and  Smith 
thought  they  had  perceived  that  the  nerves  of  the  muscles 
have  their  fibres  twisted  in  a  spiral  line. 

According  to  Messrs.  Prevost  and  Dumas,*,the  nerves  of 
the  muscles  are  perceived  in  the  following  manner  in  prefer- 
enc^e  to  any  other:  a  bit 'of  the  muscle  of  beef  is  examined  after 
being  macerated  in  pure  water,  and  in  a  dark  place;  by  throw- 
ing a  cone  of  lively  light  on  the  muscle  only,  we  distinguish 
the  colour  of  the  nerve  to  be  obviously  different  from  that  of 
the  muscle,  and  it  can  be  traced  very  far  by  means  of  a  good 
lens,  and  a  very  slender  scalpel;  the  ramifications  are  then  seen 
to  terminate  by  inserting  themselves  between  the  muscular 
fibres,  the  direction  of  which  they  cut  at  right  angles.  In  or- 
der to  observe  this  arrangement  throughout  the  whole  mass  of 
a  muscle  thin  enough  to  be  transparent/the  rectus  abdominalis 
of  the  frog  is  laid  on  a  thin  plate  of  glass,  it  is  examined  by 
illuminating  it  by  transmission  by  means  of  a  weak  magnify- 
ing glass  and  the  light  of  a  candle:  the  nerve  and  its  twigs  are 
then  perceptible,  and  may  be  distinguished  from  the  muscula^ 
fibres  and  their  direction.  In  fact,  the  trunk  of  the  nerve  con^ 
tinues  its  course  through  the  thickness  of  the  muscle  parallel 
to  its  length,  and  its  branches  separate  from  it  at  right  angles 
to  enter  between  the  fasciculi  and  the  muscular  fibres;  and  as 
they  are  all  formed  on  the  same  plan,  because  of  the  moderate 
thickness  of  the  muscle,  they  represent  a  sort  of  comb.  If  the 
muscle  be  contracted,  th'e  last  visible  transverse  fibrils  of  the 
nerve  are  seen  to  correspond  exactly  with  the  summit  of  the 
angles,  or  of  the  flexuosities  of  the  muscle. 

The  nerves,  though  numerous  and  voluminous  in  the  mus- 
cles, escape  the  sight  long  before  their  divisions  are  by  any 
means  sufficiently  multiplied  to  admit  of  their  being  distributed 
to  all  the  muscular  fibres.  Two  hypotheses  have  bee'n  imagin- 
ed to  explain  their  action  in  all  the  fibres.  Isenflamm  and  M. 

*  Unpublished  memoir. 


OP  THE  MUSCULAR   SYSTEM  IN  GENERAL..  419 

Carlisle  suggest  that  the  nerves,  at  their  termination,  are  diffus- 
ed in  the  cellular  tissue  of  the  muscles,*nd  that  this  tissue  par- 
ticipates of  the  conducting  property  of  the  nerves.  Reil  admits 
the  nerves  possess  a  sphere  of  activity  extended  beyond 
termination,  and  which  he  calls  nervous  atmosphere; 
these  are  suppositions  which  shall  be  examined  hereafter. 

§  663.  The  greater  number  of  the  muscles  indeed,  have  the 
extremities  of  their  fibres  attached  to  ligamentous  tissue,  through 
the  medium  of  which  their*action  is  transmitted  more  or  less 
distinctly.  But  these  ligamentous  parts  are  much-  more  dif- 
fused in  the  exterior  than  the  interior  muscles. 

§  664.  The  colour  of  the  muscles  varies  greatly:  those  of 
the  invertebrate  animals  and  those  of  the  cold  blooded  verte- 
brated  animals  are  white;  those  of  birds,  mammiferous  ani- 
mals and  man  are  some  of  them  reddish,  of  the  tint  generally 
known  by  the  name  of  flesh  colour;  the  others  are  of  a  grayish 
white:  the  shade  varies  very  much  in  all;  it  varies  also  ac- 
cording to  different  circumstances,  existing  before  or  after 
death.  The  colour  is  removed  by  washing  or  maceration; 
it  appears  moreover  the  lighter  in  proportion  as  the  muscle, 
the  bundle  or  the  fasciculi  is  minute,  and  on  the  contrary, 
the  deeper  in  proportion  as  the  size  of  the  mass  is  greater. 
In  thin  slices,  muscular  substance  is  semi-transparent. 

The  consistency  of  the  muscle  greatly -varies,  even  in  the 
dead  body,  as  well  from  the  causes  which  have  acted  before  or 
after  death,  and  will  be  examined  when  we  come  to  speak  of 
their  irritability.  In  general,  the  muscular  fibre  is  soft,  hu- 
mid, slightly  elastic,  and  easily  torn  in  the  cadaver. 

§  665.  Muscular  flesh  exposed  in  thin  slices  to  the  action 
of  a  current  of  dry  air,  or  of  a  stove,  loses  more  than  half  of 
its  weight,  becomes  brown,  more  transparent,  and  very  hard. 
On  the  contrary,  if  it  be  put  in  cold  water  frequently  renew- 
.ed,  the  flesh  loses  its  hue  entirely,  and  assumes  a  straw  colour- 
ed tint;  maceration  moreover  softens  and  swells  it. 

Alcohol,  diluted  acids,  the  solution  of  corrosive  sublimate; 
those  of  alum,  common  salt,  and  nitrate  of  potash,  augment 
the  consistency  of  the  muscle,  slightly  contract  it,  favour  its 


420  GENERAL  ANATOMY. 

separation  into  fibres  and  change  its  colour  in  various  manners. 
Alcohol  renders  it  paH;  alum  turns  it  brown  and  hardens  it 
greatly:  nitrate  of  potash  and  common  salt  render  it  slightly 
red,  and  having  at  first  hardened  it,  afterwards  soften  it,  espe^ 
cially  the  first,  while  it  retards  its  decomposition.  According 
to  the  observations,  as  yet  unpublished,  of  Mr.  Britonneau, 
and  those  of  Mr.  Labaraque,  the  solution  of  chlorid  of  calcium 
at  a  suitable  degree  of  concentration,  preserves  the  consistency, 
the  flexibility  and  other  natural.qualities  of  muscular  flesh  and 
the  other  soft  parts. 

§  666.  Muscular  substance  treated  with  cold  water,  yields  to 
it  colouring  matter,  somewhat  differing  from  that  of  the  blood, 
some  gelatin  and  albumen,  and  an  extractive  matter  noticed 
by  Thouvenel. 

'  Submitted  to  the  action  'of  boiling  water,  flesh  furnishes  a 
greater  portion  of  these  same  substances,  and  moreover  some 
fat.  The  muscle  thus  treated,  and  exhausted  by  the  pro- 
longed action  of  water,  there  remains  only  some  discoloured 
fibres,  insoluble  in  water,  'easily  separated,  by  desiccation  be- 
coming brittle,  and  having  all  the  properties  of  fibrine.  Mus- 
cular substance  being  calcined,  leaves  about  one  twentieth  of  its 
weight  of  saline  matter. 

It  follows  from  these  facts,  observed  by  Thouvenel,  Four- 
cro)r,  M.  Thenard  and  others,  that  the  muscles  are  principally 
composed  of  fibrine,  that  they  also  contain  -albumen,  gelatin, 
extractive,  osmazome  of  M.  Thenard,  phosphates  of  soda,  am- 
monia and  lime,  and  carbonate  of  lime. 

•   These  observations  have  been  particularly  made  on  ox's 
flesh;  but  as  the  chemical  properties  of  the  muscles  present 
differences  even  in  animals  of  a  nature  very  similar,  they  are* 
not  perhaps  exactly  applicable  to  man. 

§667.  During  life,  the  muscles  enjoy  an  active  force  or 
property,  commonly  designated  under  the  names  of  muscular, 
irritability,  muscular  force,  or  myotility. 
•    §  668.  Muscular  action*  has  been  the  subject  of  much  labour 

'See  Fr.  Glisson,  anaJt.  Jiepatis.  Lend.  1654.— Swammerdam,  Biblia.nat.,, 


.  OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  421 

and  research  on  the  part  of  Haller,  of  several  physiologists 
anteripr  to  him,  and  of  a  great  number  of  his  cotemporaries 
and  of  his  successors. 

The  study  of  the  muscular  action  comprehends:  1st,  that  of 
the  phenomena  of  this  action;  2d,  that  of  its.  conditions;  3d, 
that  of  its  principle  or. cause,  and  4th,  that  of  its  effects. 

§  669.  The  phenomena  of  the  muscular  action  which  are 
best  known  are  the  following:  the  muscle  in  action  becomes 
shortened,  tumefied,  hardened;  we  are  uncertain  whether  or 
not  its  volume  "changes;  its  colour  does  not  vary;  it  presents 
wrinkles  or  folds  on  its  surface;  its  fibres  and  fasciculi  are 
often  in  a  tremulous  or  oscillating  state  depending  on  its  alter- 
nate contraction  and  relaxation:  it  acquires  great  force  and 
manifest  elasticity:  these  are  the  phenomena  of  contraction; 
the  most  remarkable  of  these  facts  indeed,  is  the  shortening  of 
the  muscle.  When  the  action  ceases,  all  these  phenomena 
disappear,  and  the  muscle  is  then  in  a  state  of  relaxation. 

torn.  ii. — Haller,  departibuscorp.  ham.  irriiabiKbuSf  in  comm.  Getting,  torn, 
ii,  et  in  nov.  comm.  Getting1,  torn.  iv.-&M?moires  sur  la  nature  sensible  et  irri- 
table des parties  du  corps  humain.  Laus.  1756-59. — Petrini,  sull  'inscnsib.  e 
irritab.  dissert-  transp.  Iloma,  1754. — Fabri,  sull  insensitiva  e  irrit.  opulscol. 
raccolti.;  Bonon,  1757-59. — A.  G.  Weber,  de  initiis  acprogr.  doctr.  irritnb., 
etc,  Halx,  1783. — J.  L.  jGautier,  (prses.  JReil.}  da  Irritabil.  notione,  etc. 
ftalx,  1793.— Croonian-^  lectures  on  muscular  motion,  in  Philos.  Trans.  1738. 
1745,  1747,  1751,  1788,  1795,  1805,  1810,  1818,  &c.— J.  Chr.  A.  Claras, 
der  Krampf.  Lips.  1822. — Lucae,  G-rundlinien  einer  physiol.  der  irrilabilitat 
des  menschlicheu  organismus,  in  Mechel's  Arcli.  B.  iii. — G.  Blane,  On  muscu- 
lar motion,-  Lond.  1788,  et  in  select.  Dissert.,  etc.  Lond%  182%. — :BarzeJotti, 
Esamc  di  alcune  moderne  teorie  alia  causa  prossima  della  contrazione  musco- 
lartj  Sienna,  1796,  et  in  ReiPs  Jirchiv.  B.  vi. — H.  Mayo,  Anal,  and  Physiol, 
commentaries)  No.  1.  Lond.  1822. 

f  Dr.  W.  Croone,  who  died  in  1684,  left  the  plan  of  two  lectures  to  be 
instituted,  the  .one  at  the  Colleg-e  of  Physicians,  on  the  nerves  and  brain: 
the  other,  which  was  to  be  annual,  at  the  Royal^ Society  of  London,  on  the 
nature  and  laws  of  muscular  motion.  The  latter  is  still  continued,  and  has 
given  rise  to  several  excellent  papers,  both  on  the  texture  and  action  of 
the  muscles.  Several  of  these  lectures  are  not  consigned  in  the  Philosophi- 
•  cal  Transactions. 


422  GENERAL  ANATOMY. 

Are  the  muscles  also  susceptible  of  active  elongation?  Nu- 
merous facts  have  been  cited  in  favour  of  this  opinion.  Among 
them,  there  are  some*  which  prove  nothing  in  its  favour; 
others,  reported  by  Bichat,  Autenrieth,  Sprengel  et  Meckel, 
leave  the  question  still  at  least  undecided. 

It  has  been  also  admitted  that  there  is  in  the  muscles  &  fixed 
situation,  or  an  action  in  which  they  are  neither  contracted 
nor  elongated.  The  same  may  be  said  of  this  phenomenon  as 
of  the  preceding.  , 

.§  670.  The  contraction  or  shortening  being  the  fact  best 
established  in  the  muscular  action,  it  must  be  examined  in  de- 
tail, as  well  -as  its  concomitant  phenomena. 

The  muscle  augmenting  in  thickness  at  the  same  time  that 
it  is  shortened,  the  simultaneous  occurrence  of  these  two  phe- 
nomena, has  given  rise  to  a  question  that  has  greatly  occupied 
the  attention  of  physiologists,  and  which  is  not  yet  entirely 
resolved:  it  is  to  ascertain  if  the  volume  of  the  muscles  changes 
at  the  moment  of  their  contraction. 

The  experiments  of  Svvam|nerdam,  Glisson,  Goddart  and 
Erman,  on  the  diminution  of  the  size  of  the  muscles  during 
their  contraction,  does  not  prove  decidedly  that  this  dimi- 
riution  takes  place.  The  same  obtains  with  respect  to  the 
experiments  and  the  reasonings  of  Amberger,  Prochaska  and 
Mr.  Carlisle  in  favour  of  augmentation;  they  leave  the  ques- 
tion equally  undecided.  It  is  very  probable,  according  to 
the  observations  and  experiments  of  Mr.  G.  Blane,  Barzelotti, 
Mr.  Mayo  and  Messrs.  Prevost  and  Dumas,  thai  there  is  no 
change  of  volume,  and  this  accords  with  the  opinion  of  Soem- 
mering,  Sprengel  and  Meckel;  the  shortening  and  swelling  of 
the  muscle  mutually  compensating  each  other. 

§  671.  The  shortening  manifests  itself  by  various  effects. 
The  swelling  is  evident  to  the  simplest  observation.  The*  in- 
duration is  sensible  to  the  touch. 

§  672.  The  colour  of  the  muscles  suffers  no  change  during 
the  contraction.  It  has  been  thought  that  the  contrary  was 

*  V.  Barthez,  nouv.  £Um.  de  la  science  de  Fhomme,  tome  i. 
f  Barthez,  ibid. 


OP  THE  MUSCULAR  SYSTEM  IN  GENERAL.  423 

perceived  on  examining  the  heart  of  young  animals  while  in 
action;  the  apparent  change  of  colour  is  only  owing  to  its 
transparency. 

§673.  Many  physiologists  have  ascribed  the. muscular  ac- 
tion to  the  accumulation  of  blood  in  the  muscles,  either  in  the 
interior  itself,  or  the  invervals  of  the  fibres;  others  to  causes 
analogous,  all  of  which  suppose  an- augmented  activity  of  the 
circulation  during  the  muscular  action.  Haller  has  already 
offere^  many  objections  to  these  hypotheses.  There  is  no 
direct  proof  of  the  afflux  of  blood  in  the  muscles  during  their 
action.  The  experiments  of  Barzelotti.  moreover  prove  that 
the  contraction  'of  the  muscles  of  the  frog?  excited  by  galvan- 
ism, can  take  place  after  death:  1st,  when  the  blood  no  longer 
circulates  in  the  vessels;  3d,  when  the  blood  is  even  congealed, 
and  3d,  when,  in  fine,  the  vessels  are  deprived  of  blood  altoge- 
ther. The  question,  it  is  true,  arises  as  to  the  cadaverous  con- 
tractions exerted  by  galvanism;  but  other' facts  prove  again, 
that  the  presence  of  blood  in  the  vessels  of  the  muscles  is  not 
necessary  to  their  contraction.  Nevertheless,  it  is  known  that, 
when  there  is  fluid  blood  in  a  muscle,  contraction,  even  after 
death,  puts  the  blood  in  motion,  as  if  by  a  kind  of  exposition. 

§  674.  The  fibres  which  were  straight  during  the  state  of 
relaxation,  bend  during  contraction,  forming  very  regular 
sinuosities.  These  sinuosities  or  folds,  before  perceived'  by 
numerous  observers,  have  been  carefully  examined  by  Messrs. 
Prevost  and  Dumas,  who  have  recognised  these  zigzags  a* 
being  always  produced  in  the  same  manner,  and  that  the  apex 
of  the  angles,  which  are  the  points  of  the  fibre  that  approach 
each  other  outside  of  the  line  of  con-traction,  are  also  those 
where  the  last  traj^verse  ramifications  of  the  nerves  ter- 
minate. 

§  675.  During  the  contraction  of  the  muscles  there  exists  a 
continual  fibrillar  agitation*  in  their  thickness;  some  of  the 
fibres  contract,  while  others  are  relaxed.  It  is  to  this  cause 
that  we  must  ascribe  the  noise  that  is  heard  when  the  finger 

*  Roger,  de  perpetud  fibr.  must,  palpitatione;  Gott,  1760.-r-Wollaston, 
.Croonian  Lecture,  in  Philos.  Trans.;  Ann.  1810. 
55 


424  GENERAL  ANATOMY. 

is  applied  to  the  orifice  of  the  auricular  canal,  as  well  as  that 
which  is  perceived  by  the  application  of  the  stethoscope  on 
the  muscle  in  action.  This  phenomenon  is  principally  and 
perhaps  solely  rendered  appreciable  in  a  muscle  where  the 
action  is  ke'pt  up  for  some  time.  It  has  only  been  observed 
to  exist,  either  by  the  help  of  the  sight  or  hearing,  in  the  exte- 
rior muscles,  and  in  the  heart. 

§  676.  Certain  muscles  are  capable  of  partial  contraction. 
This  is  at  least  seen  in  the  experiments  on  living  animals,  and 
in  some  cases  of  convulsion  of  the  subcutaneous  muscles.  Is 
this  peculiar  to  the  muscles  which  have  several  nerves? 

§  677.  The  rapidity  as  well  as  the  force  of  contraction 
are  extremely  great;  the  rapidity  is  very  great  in  the  action 
of  running,  in  that  of  speaking  fastj  in  that  of  playing  on 
stringed  instruments,  &c.  This  rapidity,  in  some  cases,  may 
be  carried  to  less  than  a  third  in  point  of  time.  The  force  of 
the  muscles  when  in  action  is  enormous,  and  is  sometimes 
sufficient  to  rupture  the  tendons -or  the  bones,  parts  of  the 
body  so  capable  of  resisting  rupture;  it  is  always  in  propor- 
tion to  the  number  of  muscular  fibres,  each  of  which  possesses 
its  own  force,  which  is  a  fraction  of  the  total  force.  The  elas- 
ticity of  the  contracted  muscles  is  particularly  manifest  in  the 
production  of  the  voice. 

§  678.  It  is  difficult  to  determine  the  extent  .of  the  contrac- 
tion; it  has  been  attempted  on  the  principle  of  certain  hypo- 
thetical ideas  as  to  the  form  of  the  primitive  fibres,  and  it  has 
thus  been  estimated  at  one  third  the  length  of  the  fibre.  Direct 
observation  demonstrates  that  Jhe  shortening  of  the  contracted 
fibre,  in  the  exterior  muscles,  is  the  fourth  of  its  length;  Messrs. 
Prevost  and  Dumas  have  arrived  at  the  same  result  by  mea- 
suring the  angles,  which  are  formed  during.co.ntraction.  How- 
ever this  may  be,  the  extent  of  the  contraction  is  always  in 
proportion  to  the  length  of  the  muscular  fibres.  When  nothing 
is  opposed  to  the  contraction  of  the  muscle,  it  is  capable  of 
producing  a  very  great  .shortening,  examples  of  which  are 
seen  in  cases  of  fracture,  and  loss  of  substance  in  the  bones 
and  members. 

§  679.  The  conditions  of  muscular  action  are  the  life  of  the 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  425 

muscle  and  its  communication  with  the  circulatory  and  nerv- 
ous centres,  its  integral  state,  and  the  action  of  an  exciting 
or  stimulating  influence. 

Muscular  action  can  not  occur  unless  the  circulation  takes 
place  in  the  muscle;  should  the  arteries  or  principal  veins  of 
a  part  of  the  body  be  tied,  its  muscular  action  is  considerably 
weakened.  The  muscles,  in  order  to  act,  must  also  commu- 
nicate through  the  nerves,  with  the  nervous  centre;  the  inter- 
ruption of  this  communication  arrests  the  muscular  action 
more  or  less  suddenly.  It  invariably  and  instantly  stops  the 
influence  of  the  nervous  centre;  but  the  muscle  remains  irrita- 
ble from  causes  that  act  on  it,  or  on  the  nerve  to  which  it  is 
still  attached. 

§  680.  The  muscle  must  be  in  its  integral  state;  the  contu- 
sion of  the  muscles,  the  inflammation  of  their  cellular  sheaths, 
the  accumulation  of  fat  in  the  intervals  of  the  fasciculi,  &c., 
are  so  many  tircumstances  that  more  or  less  oppose  -the  mus^ 
cular  action.  The  excessive  distention  of  the  muscular  fibres 
is  sufficient  to  prevent  their  action;  this  is  not  altogether  the 
case  with  respect  to  their  contraction.  An  extreme  degree  of 
heat  or  cold,  the  immediate  application- of  opium  on  the  mus- 
cles, and  many  other  substances,  diminish  the  muscular  irri- 
tability in  general,  but  have  little  effect,  however,  on  galvanic 
susceptibility. 

§  681.  To  bring  the  muscle  at  all  into  action,  it  must  be  ex- 
cited by  some  stimulant.  The  stimulants  of  muscular  action 
are:  1.  Volition,  or  the  action  of  the  will;  it  acts  on  the  muscles 
through  the  medium  of  the  nerves,  but  it  only  serves  as  a 
stimulant  to  certain  particular  muscles,  which  for  this  reason 
are  called  voluntary  muscles;  2.  Emotion  or  passion  which  acts 
by  the  same  means,  but  the  action  of  which  is  extended  to  all 
the  muscles;  3.  The  irritation  of  the  encephalon,  of  the  spinal 
marrow,  or  of  the  nerves,  which  in  the  first  case,  also  acts  on 
all  the  muscles,  but  with  more  or  less  energy;  4.  The  stimula- 
tion of  some  determined  part,  of  the  skin  or  the  mucous  mem- 
brane, more  or  less  remote  from  the  muscles;  5.  That  of  the 
membrane  which  immediately,  covers  the  muscles,  as  the  in- 
•  ternal  membrane  of  the  heart,  the  cellular  sheath  of  the  mus- 


426  GENEKAL  ANATOMY. 

cles,  the  serous  membrane  of  the  abdomen,  &c. ;  6.  Lastly, 
the  direct  irritation  of  the  muscle  itself:  it  remains  doubtful, 
in  this  case,  whether  the  exciting  cause  acts  immediately  on 
the  muscular  fibre,  or  through  the  medium  of  the  nerves. 
What  renders  this  last  supposition  the  more  probable,  is  that 
the  irritation  of  a  part  of  a  muscle  produces  the  contraction  of 
the  entire  muscle  itself. 

•  §  682.  The,  cause  of  muscular  action  is,  like  that  of  all  or- 
ganic action,  almost  impossible  to'determine:  we  know  the 
phenomena  and  conditions,  beyond  that,  all  is  mere  hy- 
pothesis. This  cause  has  been  ascribed  to  the  action  of  the 
nerve,  to  that  of  the  blood,  to  the  reciprocal  action  of  the 
nerve  and  the  blood  in  the  muscle;  and  according  to  the  doc- 
trines prevailing  at  different  periods,  these  opinions  have  given 
birth  to  a  great  many  different  hypotheses,  none  of  them  have 
accounted  for  the  augmentation  of  the  power  of  cohesion  of  the 
muscle.  .  It  is  evident  that  during  contraction  there  is  a  mo- 
mentary increase  of  molicular  attraction  between  the  particles 
of  the  fibre.  If  the  plaited  form  assumed  by  the  fibre  be  con- 
sidered, as  well  as  the  connexion  of  the  nervous  filaments  with 
their  plaits,  it  may  readily  be  conceived  that  the  nervous  in- 
fluence must  share  largely  in  the  phenomenon  of  contraction. 

§  683.  Is  irritability  a  power  inherent  in  the  fibrinous  sub- 
stance of  the  muscle,  and  does  the  nervous  action  only  there 
take  place  like  any  other  excitant  causing  contraction?  In  this 
hypothesis,  the  nerves  would,  in  the  voluntary  muscles,  only 
fulfil  the  function  of  irritating  .them;  and  with  respect  to  the 
muscles  which,  as  the  heart,  do  not  contract  voluntarily, 
the  nervous- action  would  not  manifest  itself  under  ordinary 
circumstances.  Or,  on  the  other  hand,  has  irritability  its  only 
source  in  the  nervous  system?  By  this  hypothesis,  the  nerves 
would  fulfil,  with  regard  to  the  voluntary  muscles,  the  double 
office  of  rendering  them  irritable  and  of  causing  them  to  con- 
tract; and,  with  regard  to  the  involuntary  muscles,  the  con- 
traction of  which  is  determined  by  local  stimulants,  it  would 
render  them' only  predisposed  to  this  contraction.  Or,  lastly, 
have  the  muscles  an  inherent  power,  (visinsita)  and  a  power 
borrowed  from  the  nervous  action  (vis  nervea)?  It  is  almost 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  427 

impossible  to  answer  these  questions,  or  to  choose  between 
these  hypotheses  with  any  reasonable  motive  of  preference. 
§  684.  The,  effects  of  muscular  actfcn  in  the  living  body4  are 
to  produce  or  to  prevent  the  movement  of  the  solid  and  liquid 
parts,  or  even  of  the  whole  body,  as  the  case  may  be. 

The  modes  according  to  which  the  muscles  exercise  their 
action,  may  be  reduced  to  two:  1.  The  two  extremities  of  the 
fibres  in  action  may  remain  equally  stationary,  as  in  the  ac- 
tion of  the  diaphragm,  the  muscles  of  the  abdomen,  the  bucci- 
nator, &c.;  or  be  equally  moveable,  as  in  the  sphincters,  the 
annular  fibres  of  the  stomach,  the  intestines,  &c.;  2.  One  ex- 
tremity of  the  fibres  in  action  is  more  fixed  than  the  other,  so 
that  the  more  moveable  one  is  (frawn  towards  the  other,  as  in 
the  greater  part  of  the  muscles  of  the  members;' particularly  in 
those  of  the  fingers  and  toes;  or  else  one  extremity  is  abso- 
lutely stationary,  and  the  other  absolutely  i&oveablej  as  in  the 
muscles  of  the  eye,  the  soft  palate,  &c. 

§  685.  The  actions  of  the  muscles  that  naturally  take  place 
in  the  body,  may  be  divided  into  two  classes:  voluntary  and 
involuntary. 

The  voluntary  actions  are  those  of  all  the  muscles  that  ser.ve 
the  purpose  of  the  skeleton  both  when  stationary  or  in  motion, 
that  contribute  to  the  movements  of  the  larynx,  and  to  those 
of  the  organs  of  sensation.  All  these  muscles  receive  their 
nerves  directly  from  the  spinal  marrow. 

The  involuntary  actions  may  be  subdivided  into  three  or- 
ders; some  are  produced  by  the  stimulus  acting  across  a  thin 
membrane  which  immediately  covers  the  muscles;  such  are 
the  movements  of  the  alimentary  canal,  of  the  bladder,  of  the 
heart,  &c. ;  others  are  produced  by  stimuli  of  an  analogous 
kind,  but  which  are  propagated  by  means  of  a  connexion  with 
many  other  muscles:  such  are  the  movements  of  deglutition, 
respiration,  coughing,  sneezing,  fecal  excrementation,  emis- 
sion of  sperm,  urinating,  accouchement,  &c.  The  others  are 
the  movements  of  emotion  or  passion,  such  as  laughing,  cry- 
ing out,  &c. 

Among  the  actions  or  movements  of  this  second  class,  some 
have  been  considered  as  semi-voluntary,  or  .as  constituting  an 


428  GENERAL  ANATOMY. 

intermediate  class  of  mixed  movements.  It  is  in  fact  extreme- 
ly difficult  to  establish  a  well  marked  distinction  between  the 
voluntary  movements,  tWlt  is  to  say,  those  under  the  perfect 
control  of  the  will,  and  the  involuntary  movements;  for  on  the 
one  hand,  there  are  few  functions  over  which  the  will,  and 
above  all  the  passions,  do  not  exercise  their  empire;  and  on 
the  other,  many  of  the  voluntary  movements  become,  by  as- 
suetude,  almost  involuntary;  such,  for  example,  are  the  move- 
ments of  the  members  which  take  place  without  conscious- 
ness, and  without  exercise  of  the  will  during  sleep;  such  are 
those  of  the  eyelids  which  take  place  even  in  opposition  to  the 
will,  when  a  foreign  body  approaches  the  eye;  the  difficulty 
or  the  impossibility  of  moving  simultaneously  the  superior  or 
inferior  members,  or  the  eyes,  in  a  direction  opposed  to  that 
which  they  are  ordinarily  accustomed  to,  are  moreover  of  this 
character.  The  accidental  irritation  of  the  muscles,  of  the 
nerves,  or  of  the  nervous  centre,  sometimes  renders  the  con- 
traction of  the  exterior  muscles  altogether  involuntar}r;  other 
affections  render  them  immoveable  in  spite  of  the  will.  As  to 
the  influence  of  the  will  on  the  movements  regarded  as  in- 
voluntary, it  is  evident  in  those  of  respiration,  of  vomiting, 
and  .ruminating;  it  even  appears  to  be  sometimes  extended  to 
the  movements  of  the  heart,  to  those  of  the  uterus,  the  iris  and 
the  skin;  it  is  true,  that  the  influence  of  the  passions  on  the 
will  itself  must  not  be  forgotten. 

The  movements  that  have  been  regarded  as  mixed,  are  more 
especially  those  which,  occurring  in.  general  unconsciously, 
and  without  the  exercise  of  the  will,  may  be  modified  by  the 
latter;  of  this  character  are  those  of  the  diaphragm.  This  name 
is  not  so  generally  given  to  those  which  being  habitually 
voluntary,  are  exercised  by  habit  and  association,  without  be- 
ing directed  by  the  will,  as  movements  by  which  the  superior 
members  are  balanced  in.  walking. 

It  is  to  be  remarked  that  apoplexy  and  the  other  cerebral 
affections  generally  paralyze  the  voluntary  muscles  only. 

§  686.  The  varied  muscular  movements  which  take  place  in 
the  living  body,  are.  in  general  either  connected  with  each 
other,  in  order  to  produce  an  identical  action,  or  opposed  to 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  429 

each  other,  to  produce  contrary  actions:  in  the  first  case,  the 
muscles  are  called  congeneric;  in  the  second  antagonist.  An- 
tagonism is  much  the  most  evident  in  the  exterior  muscles, 
as,  for  instance,  it  is  seen  in  the  flexors  and  extensors;  it  is 
less  strongly  marked  in  the  interior  or  automatic  muscles; 
nevertheless,  it  is  not  altogether  foreign  to  them;  'opposition 
of  the  automatic  and  arbitrary  muscles  occurs  at  the  natural 
orifices,  as  is  perceived  between  the  excretory  muscles,  which 
are  involuntary,  and  the  sphincter  muscles  which  are  volun- 
tary. Antagonism  every  where  presents  this  remarkable  phe- 
nomenon, that  the  Contraction  of  some  muscles  is  accompanied 
by  the  relaxation  of  another.  The  Congeneric  or  associated 
muscles  present  another  important  phenomenon,  which  is,  that 
their  contraction  is  simultaneous,  and  that,  when  a  stimulus 
is  confined  to  one  only,  the  rest  nevertheless  come  into  action: 
thus  when  the  throat,  the  orifice  of  the  larynx,  the  anterior 
angle  of  the  vesical  trigon,  &c.,  are  stimulated,  all  the  muscu- 
lar powers  exercised  in  vomiting,  in  coughing,  or  in  urinat- 
ing, &c.,  are  brought  into  action  by  the  law  of  association 
of  the  congenerous  muscles,  but  at  the  same  time  aixl  in  con- 
formity with  the  law  of  antagonism.  In  the  last  case  the 
sphincter  and  constrictor  muscles  of  the  neck  of  the  bladder, 
and  of  the  ureter,  are  relaxed. 

§  687.  The  muscles  continue,  some  time  after  death,  and 
after  circulation  ceases,  to  be  irritable  and  contractile  by  means 
of  divers  stimuli.  All  the  muscles  do  not  preserve  their  irri- 
tability during  the  same  period;  neither  do  they  suddenly  lose 
their  susceptibility  to  contraction,  but  cease  at  first  to  be  e£- 
citable  by  certain  stimuli;  the  anterior  state  of  health,  the  kind 
of  death,  the  exterior  circumstances  before  death,  have  a  great 
influence  on  the  duration  of  the  muscular  irritability.  Galen, 
Harvey,  and  Haller,  knew  that  the  heart  is  in  general  the 
ultimum  moriens.  Haller  had  established  an  order  of  cessa- 
tion of  irritability  in  the  different  muscles,  and  also  perceived 
several  varieties  in  -that  order.  Zinn,  Zimmermann,  Ader, 
Froriep,  and  particularly  Nysten,  have  particularly  studied 
this  subject.  The  varieties  perceived  by  Haller,  depend 
greatly  on  the  nature  of  the  excitant;  for  instance;  the  heart 


430  GENERAL  ANATOMY. 

remains  irritable  much  longer  than  any  other  muscle,  by  the 
application  of.  mechanical  agents,  and  the  muscles  of  the 
skeleton,  on  the  contrary,  by  galvanic  irritation.  Galvanic 
irritation  acts  more  efficaciously  by  not  comprehending  the 
exterior  muscles,  than  by  comprehending  them  with  the  nerve 
in  the  galvanic  circuit.  The  contrary  occurs  with  the  inte- 
rior muscles. 

The  order  established  by  Nysten,  with  respect  to  the  suc- 
cessive extinction  of  irritability  in  the  bodies  of  decapitated 
individuals,  is  as  follows:  1st,  the  aortic  ventricle  of  the  heart; 
2d,  the  large  intestine,  the  small  intestine  and  the  stomach; 
3d,  the  urinary  bladder;  4th,  the  pulmonary  ventricle;  5th, 
the  oesophagus;  6th,  the  iris;  7th,  the  exterior  muscles;  Sth, 
the  right  auricle,  and  lastly,  the  left  auricle. 

Muscles  or  parts  of  muscles,  separated  from  the  living  body, 
retain  their  irritability  for  some  time.  They  present,  in  this 
respect,  variations  analogous  to  those  which  have  just  been 
indicated.  Contraction  under  these  two  circumstances  evi- 
dently takes  place  without  an  afflux  of  blood. 

§  688.  When  irritability  is  on  the  point  of  being  extinct  or 
exhausted  in  the  muscles,  irritation  no  longer  determines  any 
general  or  extensive  contraction  of  the  entire  muscles,  their 
bundles  or  fasciculi;  but  it  remains  limited  to  the  points  irri- 
tated, which  swell  by  the  flexuosity  of  which  it  becomes  the 
seat.  This  last  description  of  irritability  which  survives  the 
nervous  action,  appears  to  me  to  be  precisely  of  the  same  kind 
as  that  observable  in  the  fibrine.of  the  blood;  this  is  in  reality 
the  vis  insita  of  the  muscular  fibre. 

§  689.  The  kind  of  death,  the  previous  state,  and  the  sur- 
rounding circumstances,  exert  an  influence  on  the  cadaverous 
irritability.  The  state  of  paralyses  and  of  hemiplegia  does  not 
prevent  the  muscles  from  being  irritable  in  the  cadaver,  by 
galvanism.  Diseases  have  a  much  greater  influence  on  the 
cadaverous  irritability  by  their  progress  and  continuance,  than 
by  their  nature;  chronic  diseases  alter'this  property  much 
more  than  acute  ones,  and  among  the  chijpnic  diseases,  those 
in  which  nutrition  is  most  impaired,  are'most  fatal  to  muscular 
action.  The  most  muscular  persons  are  not  those  in  whom  mus- 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  431 

cular  irritability  continues  longest  after  death.  This  duration 
varies  from  one  hour  to  twenty-four  hours,  or  thereabout. 

§  690.  Finally,  after  all  irritability,  general  or  local,  has 
ceased  in  the  body  deprived  of  life,  cadaverous  stiffness  en- 
sues.(124)  It  is  an  invariable  phenomenon,  whatever  may 
have  been  said  of  it  by  Haller  and  Bichat,  but  it  varies  in  its 
intensity  as  well  as  duration.  This  contraction  or  stiffness, 
has  its  seat  in  the  muscular  system,  and  is  independent  of  the 
nervous  system;  it  takes  place  only  when  this  system  has 
ceased  to  possess  any  galvanic  irritability.  The  section  of  the 
nerves,  the  state  of  hemiplegia  and  the  oblation  of  the  nervous 
centre,  do  not  hinder  it  from  manifesting  itself.  It  is  the  last 
effort  of  muscular  contractility.  In  cold  blooded  animals,  in 
which  nervous  excitability  continues  fora  long  time,  cadaver- 
ous stiffness  occurs  late  and  continues  but  a  short  time,  where- 
as, in  warm-blooded  animals,  it  takes  place  soon  after  death 
and  continues  a  long  time;  in  which  nervous  excitability  is  of 
short  duration.  Cadaverous  stiffness  seems  to  be  analogous  to 
the  contraction  of  the  fibrinous  coagulum  of  the  blood,  and 
like  this,  only  ceases  when  putrefaction  commences.  It  may 
be  considered,  when  joined  to  the  coldness  that  always  ac- 
companies it,  as  a  certain  sign  of  death.  If  a  muscle  in  a 
state  of  stiffness  be  immersed  and  preserved  in  alcohol,  that 
stiffness  will  continue  for  an  indefinite  period. 

§  693.  Other  moving  properties  have  been  attributed  to  the 
muscles.  Galen  recognised  in  them  a  tonic  force,  indepen- 
dent of  life;  elasticity  has  likewise  been  ascribed  to  them;  Hal- 
ler ascribed  to  them  contractile  force  in  general,  as  well  as 
dead  force;  Sympson  and  Whytt  attributed  tonicity  or  tonic 
force  to  them;  Bichat,  in  addition  to  voluntary  contractility, 
and  irritability  or  voluntary  contractility,  attributed  to  them 
insensible  organic  contractility,  that  is  to  say  tonicity. 

The  muscles  are  extensible,  they  are  retractile 'also,  and  this 
independently  of  their  contraction  by  irritation.  In  the  state 
of  sleep  and  of  repose  the  muscles  furnish  generally  to  the  dif- 
ferent parts  of  the  body,  mean  attitudes  depending  on  their 
proportionate  length,  and  consequently  on  their  tension,  on 
their  force,  and  on  the  manner,  more  or  less  efficacious,  in 
56 


432  GENERAL  ANATOMY. 

which  this  force  is  applied.  The  -same  thing  takes  place  in 
paralysis  determined  artificially,  by  cutting  all  the  nerves  of 
a  member.  In  paralysis  arising  from  cerebral  affection,  and 
in  contraction  of  the  limbs,  the  attitude  is  sometimes  different ; 
the  flexion  being  sometimes  carried  to  a  great  extent.  But 
here  arises  a  doubt,  which  is,  whether  the  cause  of  paralysis 
has  been  equally  extended  to  all  the  nerves  of  the  part;  if  in- 
deed this  cause  does  not  originate  in  the  tonic  contraction  of 
some  muscles.  In  the  dead  body  the  muscles  remain  contrac- 
tile, and  give  a  determinate  attitude  to  all  parts  of  the  body, 
until  the  cadaveric  stiffness  subsides. 

§  693.  The  muscles  are  possessed  of  sensibility,  but  only  in 
a  moderate  degree.  In  the  state  of  health  they  produce  little 
more  than  the  sense  of  fatigue  during  and  after  their  action, 
when  it  has  been  prolonged.  When  the  action  has  been  very 
long  continued  and  violent,  it  produces  a  painful  sensation. 
The  same  thing  occurs  in  case  of  inflammation  of  their  tissue 
or  of  their  cellular  sheaths.  Cabanis  and  Dr.  Yelloly  have 
stated  cases  of  diseases  in  which  the  muscles  were  insensible. 

§  694.  The  circumstances  which  manifest  a  continual  change 
of  particles  in  muscular  nutrition  are  not  very  evident;  the 
fact  is  nevertheless  probable:  it  would  seem  to  be  the  globu- 
lar part  of  the  blood  that  furnishes  the  materials  for  it.  The 
effects  of  exercise  on  nutrition,  the  augmentation  and  colora- 
tion of  the  muscles,  and  the  opposite  effect  of  rest  too  long 
continued,  are  well  known.  Paralysis  produces  an  effect  still 
more  remarkable  on  their  diminution.  The  quantity  and 
quality  of  nourishment  have  a  great  influence  on  the  volume 
as  well  as  strength  of  the  muscles.  Certain  consumptive  dis- 
eases, such  as  phthisis,  have  a  strong  influence  on  muscular 
atrophy.  We  are  ignorant  whether,  in  this  case,  there  is  a 
diminution  of  volume  only,  or  a  disappearance  of  the  fibres 
altogether. 

§  695.  In  the  embryo,  the  muscular  tissue  is  not  distinct 
from  the  cellular  tissue;  they  are  confounded  in  a  common 
gelatinous  mass.  At  a  period  but  little  remote  from  the  mo- 
ment of  conception,  the  action  of  the  heart  presents  a  consi- 
derable degree  of  development  in  the  muscular  tissue  of  that 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  433 

organ.  About  two  months  after  conception,  the  muscles  of  the 
skeleton  have  acquired  distinct  fibres;  towards  the  fourth 
month  they  begin  to  execute  contractions.  According  to  Bi- 
chat,  the  muscles  of  the  foetus  possess  a  smaller  degree  of  irri- 
tability, or  at  least  less  galvanic  susceptibility,  than  that  of 
individuals  who  have  respired.  Experiments  made  by  Meckel 
on  some  animals  have  offered  results  contradictory  to  those 
of  Bichat. 

During  childhood  the  muscles  continue  small  in  volume  in 
proportion  to  the  nerves  and  adipose  tissue.  At  this  age  too, 
the  muscular  flesh  is  not  only  less  red,  but  is  more  gelatinous 
and  less  fibrinous  than  in  adult  age;  the  motions  are  easy, 
prompt  and  feeble. 

The  muscles,  which  are  of  a  vermilion  red  in  the  adult,  be- 
come pale,  yellowish  and  livid  in  old  age;  contractions  at  this 
period  become  difficult,  feeble  and  slow. 

The  irritability  and  action  of  the  muscles  in  females,  com- 
pared with  those  in  males,  present  nearly  the  same  difference 
as  those  of  the  adolescent  compared  with  those  of  the  adult: 
that  is,  a  greater  degree  of  irritability  or  susceptibility  of  move- 
ment, a  weaker  action  and  less  capable  of  a  continued  action. 

Between  the  races  of  mankind  there  exist  differences  in 
muscular  power,  which,  according  to  the  experiments  made 
by  Peron  with  the  dynamometer,  is  in  favour  of  Europeans, 
whose  health  and  strength  are  the  result  of  abundant  and 
wholesome  diet  and  habitual  occupation,  while  the  inhabitants 
of  Timor,  New  Holland,  and  Van-Diemen*s  Land,  exposed 
as  they  are  to  every  kind  of  privation,  have  less  muscular 
strength. 

§  696.  When  the  muscles  are  exposed  to  view*  by  a  wound 
of  the  skin,  the  aponeurosis  and  the  cellular  sheaths,  and  these 
parts,  are  brought  together  again  with  precision,  there  occurs 
in  the  solution  of  continuity  an  effusion  of  organizable  fluid; 
at  first  slightly  adherent  to  the  muscle  and  afterwards  esta- 
blishing an  organic  reunion.  The  same  thing  happens  when 

*  B.  Fr  Schnell,  Prass.  Auter  rieth,  de  natura  reunionis  musculorum  vol- 

neratorufii.     Tubings,  1804. 


434  GENERAL  ANATOMY. 

muscles,  divided  crosswise,  in  amputation  for  example,  are 
covered  over  again  by  the  flaps  of  skin;  only  the  agglutinating 
matter  is  from  the  commencement  very  closely  attached  to 
the  truncated  extremity  of  the  muscles.  When  muscles  are 
cut  crosswise,  and  not  covered  by  flaps  of  skin,  there  soon 
forms  at  their  extremity  suppurating  granulations,  and  after- 
wards a  cicatrice;  these  phenomena,  and  particularly  the  last, 
are  more  tardy  when  the  muscles  are  only  laterally  denuded. 
In  all  these  cases,  at  whatever  period  an  inflamed  wound  is 
examined,  whether  the  inflammation  be  adhesive  or  suppura- 
tive,  the  cellular  sheaths  of  the  muscles  and  of  their  bundles 
only  are  changed;  no  change  whatever  is  perceptible  in  the 
muscular  fibres  themselves.  It  is  proper  to  observe,  however, 
that  in  this  case  the  fibres  are  deprived  of  the  greater  part  of 
their  irritability. 

§697.  When  a  muscle  is  cut  across,  a  considerable  separa- 
tion takes  place  between  the  edges  of  the  division,  and  always 
greater  than  the  wound  sustained  by  the  skin.  When  the 
edges  of  the  external  wound  have  been  brought  together,  and 
have  united,  the  ends  of  the  muscle  remain  separated,  at  first 
filled  with  an  organizable  liquid,  which  afterwards  becomes 
vascular,  soft,  which  contracts  a  little  and  slightly  diminishes 
the  distance  which  existed  between  the  ends  of  the  muscles, 
and  at  last  becomes  more  or  less  firm  and  resisting.  This  in- 
termediate substance,  when  its  organization  is  completed,  has 
sometimes  the  appearance  of  cellular  tissue,  frequently  that  of 
ligamentous  tissue,  and  sometimes  that  of  sub-cartilaginous 
coriaceous  tissue,  but  never  that  of  muscular  tissue.  At  some 
period  of  the  formation  we  are  now  examining,  it  is  always 
found  that  the  muscular  fibres  and  fasciculi  are  foreign  to  it, 
and  that  it  is  only  the  reunion  of  the  cellular  tissue  which 
forms  sheaths  to  them.  A  muscle  which  is  reunited  in  this 
manner,  presents  a  kind  of  aponeurotic  tendinous  intersec- 
tion; it  is  a  kind  of  digastric  muscle,  the  two  bellies  of 
which  are  living  and  irritable,  whilst  the  intermediate  sub- 
stance fulfils  the  functions  of  a  tendon  which  more  or  less 
resists  or  gives  way  to  distention.  This  intermediate  sub- 
stance is  not  irritable  either  by  mechanical  stimulants  or  gal- 


OF  THE  MUSCULAR  SYSTEM  IN  GENERAL.  435 

vanism.  However,  when  irritability  is  well  manifested  and 
the  galvanic  action  is  strong,  the  irritation  applied  to  one  of 
the  parts  of  the  reunited  muscle,  is  propagated  through  the 
cicatrice,  which  however  does  not  contract  with  the  other 
part  of  the  muscle.  We  are  ignorant,  if  during  life,  and  by 
the  action  of  the  will,  the  parts  of  a  muscle  divided  across 
and  united  by  a  cicatrice,  both  contract.  It  is  evident  that 
the  greater  the  separation  between  the  muscles  at  the  time 
the  mediate  reunion  has  occurred,  that  also  the  means  of  re- 
union will  be  longer  and  more  extensible,  and  the  more  will 
the  muscles  have  lost  of  their  extension  and  power.  Under 
the  most  favourable  circumstances,  movements  at  first  are  im- 
possible and  afterwards  feeble  and  uncertain  until  the  means 
of  union  have  acquired  their  proper  degree  of  firmness. 

All  that  has  just  been  advanced  on  the  reunion  of  the  mus- 
cles that  have  been  cut  across,  is  applicable  to  their  rupture 
through  effort. 

When  a  transversal  wound  of  the  muscles  or  of  the  skin  has 
remained  separated  and  gaping,  there  is  found  throughout  its 
extent,  a  layer  of  suppurating  granulations,  and  afterwards  a 
cicatrice  more  or  less  extensive,  under  which  the  two  ends  of 
the  muscle  remain  separated. 

In  the  latter  case,  as  well  as  the  former,  the  intermediate 
substance,  too  long  and  too  extensible,  which  formed  the  re- 
union of  the  divided  muscle,  has  sometimes  been  denuded  and 
cut  out;  by  afterwards  bringing  into  contact  the  divided  parts 
and  retaining  them  in  that  state  sufficiently  long,  a  short  and 
firm  reunion  has  been  obtained  and  motion  restored  to  parts 
which  had  almost  entirely  lost  it. 

§  698.  The  muscles  are  subject  to  variations  and  to  mal- 
conformation;  monstrous  foetus,  acephalus*  and  others,  have 
been  seen,  deprived  of  all  the  muscles  or  of  all  those  apper- 
taining to  a  particular  member  at  least,  these  organs  being  re- 
placed by  infiltrated  cellular  tissue. 

We  observe  more  frequently  the  defect  or  absence  of  single 
muscles. 

*  Beclard,  Memoir es  sur  les  foetus  acfphaks. 


436 


GENERAL  ANATOMY. 


Supernumerary  muscles,  and  others  divided  into  several 
distinct  parts,  are  often  found;  muscles  united  which  ordina- 
rily are  separate;  others,  longer  or  shorter  than  is  natural, 
which  changes  their  attachments  and  modifies  their  functions; 
all  these  varieties  are  original  or  primitive. 

The  diminution  or  augmentation  of  the  volume  of  the  mus- 
cles are,  on  the  contrary,  owing  generally  to  accidental  causes. 
Repose  and  paralysis  diminishes  their  size,  exercise  augments 
it. 

Muscular  ruptures*  happen,  either  by  the  action  of  the  an- 
tagonist muscles,  or  by  another  power  which  distends  a  relaxed 
muscle,  or  by  the  action  of  the  ruptured  muscle  itself;  in  this 
last  case,  the  rupture  most  commonly  occurs  at  the  union  of 
the  tendinous  or  aponeurotic  parts  with  the  fleshy  fibres,  a 
small  number  only  of  which  are  torn.  In  case  of  rupture, 
there  occurs  a  separation,  attended  with  noise  and  pain,  and 
more  or  less  extensive  and  deep,  and  an  effusion  of  blood  more 
or  less  abundant  in  the  solution  of  continuity  and  in  the  sur- 
rounding cellular  tissue.  The  interior  muscles,  and  especially 
the  heart,  are  sometimes  ruptured  by  their  contraction. 

The  displacement!  of  the  muscles,  admitted  by  Pouteau, 
Portal,  and  other  pathologists,  is  scarcely  possible,  unless  the 
enveloping  aponeurosis  be  severed. 

§  699.  The  muscles  present  many  alterations  of  colour, 
consistency,  and  cohesion. 

In  rheumatism,  a  gelatiniform  liquid  is  sometimes  found  on 
the  surface,  in  the  interior,  and  in  the  thickness  of  the  cellu- 
lar sheaths. 

In  cases  of  long  standing  paralysis,  the  muscles  are  emaci- 
ated, white,  and  sometimes  very  fat.  We  have  already  seen 
above,  (168)  that  the  transformation  of  the  muscles  into  fat, 
was  rather  apparent  than  real.  It  results  from  the  paleness  oc- 
casioned by  the  atrophy  of  the  muscle,  conjointly  with  the 
accumulation  of  fat  between  the  fasciculi  of  fibres. 

*  J.  Sedillot,  memoire  sur  la  rupture  musculaire,  in  M^m.  et  prix  de  la 
Soc.  de  med.  de  Paris  1817. 

j-  J.  Hansbeand,  Diss.  luxationis  sic  dictse  muscularis  refutationem  aistens, 
Berol.  1814. 


OF  THE  INTERIOR  MUSCLES.  437 

Accidental  productions,  either  of  analogous  tissues  or  mor- 
bid tissues,  are  rarely  observed'  in  the  muscles.  Accidental 
bones  are,  however,  sometimes  found  in  them.  I  once  found 
a  mixed  osseous  and  cancerous  production,  occupying  the 
muscles  of  the  calf  of  the  leg.  The  leprous  cysticercus, 
cysticercus  cellulosx  of  Rudolphi,  is  sometimes  found  in  the 
muscles  of  man,  and  often  in  those  of  swine.  Accidental 
production  of  the  muscular  tissue  is  very  rare,  if  indeed  it 
ever  takes  place.  An  affinity  has,  however,  been  established 
between  the  sarcoma  and  the  muscular  flesh.  It  is  also  said 
that  accidental  muscular  productions  have  been  seen  in  the 
serous  membranes,  in  the  bones,  and  in  the  ovaries:  it  appears 
that  the  observers  have  suffered  themselves  to  be  deceived  by 
appearances. 

The  development  of  the  muscular  texture  in  the  uterus, 
during  pregnancy,  and  the  disappearance  of  that  texture  after 
accouchement,  is  somewhat  analogous  to  an  accidental  produc- 
tion. 

§  700.  The  functions  of  the  muscles  present  varieties  and 
alterations,  some  of  which  have  their  seat  and  their  cause  in 
the  muscular  tissue  itself,  and  others  in  the  nervous  system. 
These  varieties  and  these  changes  are,  for  the  most  part,  dif- 
ferent in  the  two  species  of  muscles,  and  almost  all  are  pecu- 
liar to  the  full,  external,  voluntary  muscles,  or  to  those  of  the 
animal  functions. 


SECTION  II. 

OF  THE  INTERIOR  MUSCLES. 

§  701.  These  muscles,  which  are  also  called  hollow  muscles, 
involuntary  muscles,  and  muscles  of  vegetative  or  organic 
functions,  have  no  name  appropriated  to  themselves,  each  of 
them  bears  that  of  the  organ  it  concurs  in  forming. 

§  702.  These  muscles  are,  1,  the  heart;  2,  those  which  dou- 
ble the  mucous  membrane  of  the  alimentary  passages  through- 


438  GENERAL  ANATOMY. 

out  their  extent;  those  which  line  the  urinary  and  genital  pro- 
longation of  the  same  membrane,  form  the  bladder,  the  sper- 
matic vesicles,  and  the  uterus;  those  of  the  pulmonary  pro- 
longations of  this  membrane  which  form  the  bundles  of  the 
trachia  and  bronchse.  The  sphincters,  which  are  found  at  the 
orifices  of  the  alimentary  canal  and  the  urinary  and  genital 
passages,  may  be  regarded  as  intermediate  to  the  two  classes 
of  muscles.  Nearly  the  same  is  the  case  with  respect  to  the 
texture,  and  more  especially  the  functions,  of  the  muscles  of 
the  skeleton,  which  are  subservient  to  digestion,  respiration, 
generation,  and  the  urinary  excretion.  There  is  not,  then, 
any  very  marked  distinction  between  the  two  classes  of  mus- 
cles. 

§  703.  The  muscles  in  question  are  placed  in  the  interior; 
some  situated  immediately  under  the  internal  tegument,  and 
in  particular,  the  heart,  is  situated  very  deeply  and  distant 
from  the  two  surfaces,  of  which  it  is  entirely  independent. 

The  volume  of  these  muscles  is  very  inconsiderable  when 
compared  with  that  of  the  exterior  muscles;  they  all  form  the 
parietes  of  canals  and  of  reservoirs. 

§  704.  These  muscles  are  disposed  in  layers  or  in  bundles 
crossing  each  other. 

Throughout  the  whole  extent  of  the  alimentary  canal,  there 
are  circular  or  annular  fibres,  and  longitudinal  fibres,  each 
forming  a  distinct  plane,  more  or  less  complete  and  thick. 

In  the  reservoirs,  as  well  as  in  the  heart,  the  fibres  are  dis- 
posed in  layers  and  bundles  which  cross  each  other  obliquely, 
they  have  an  arched  form,  the  extremities  of  which  are  fixed 
to  the  sides  of  the  aperture  of  the  organ.  The  bundles  of 
fibres  in  these  organs  cross  each  other,  and  are  united  in  the 
manner  of  plexuses.  This  arrangement  is  less  marked  in  the 
alimentary  canal,  where  the  muscular  layers  cross  each  other 
at  right  angles. 

The  muscular  fibre  of  the  interior  muscles  is  of  a  grayish 
white  in  most  of  them,  and  red  in  the  heart  only.     This  fibre 
differs  in  no  other  respect  from  that  of  the  exterior  muscles. 
The  uterus  alone  in  this  respect  presents  a  well-marked  differ 
ence,  and  characters  entirely  peculiar. 


OF  THE  INTERIOR  MUSCLES.  439 

§  705.  The  cellular  tissue  of  the  interior  muscles  is  not  so 
abundant,  but  is  more  compact  than  that  of  the  other  muscles. 
Fibrous  or  ligamentous  tissue  is  only  found  in  the  heart,  where 
it  forms  rings  for  the  orifices  of  the  ventricles,  cords  or  ten- 
dons for  the  fleshy  columns  of  these  cavities,  aponeurotic  ex- 
pansions which  constitute  in  a  great  measure  thetricuspid  and 
bicuspid  valves  of  the  auriculo-ventricular  orifices,  and  cords 
in  the  borders  of  the  semi-lunar  valves  of  the  arterial  orifices. 
Bichat,  who  only  speaks  of  the  tendinous  cords  of  the  fleshy 
columns,  had  before  indicated  that  tbere  exists  differences  be- 
tween them  and  the  tendons.  In  the  other  parts  nothing  is 
found  analogous  to  the  ligamentous  tissue,  except  the  submu- 
cus  fibro-cellular  tissue,  to  whif  h  are  attached  the  subjacent 
muscular  fibres. 

The  interior  muscles  appear  to  possess  more  blood-vessels 
than  the  exterior.  M.  Ribes,  however,  asserts  the  contrary. 
The  greater  part  of  the  nerves  of  these  muscles,  which  how- 
ever are  not  abundant,  belong  to  the  great  sympathetic;  seve- 
ral are  furnished  by  the  pneumo-gastric,  and  some  few  by  other 
nerves  of  the  spinal  marrow. 

§  706.  The  irritability  of  the  interior  muscles  presents  the 
same  phenomena  as  that  of  the  other  muscles,  except  the 
fibrillary  agitation,  which  has  only  been  observed  to  exist  in 
the  heart. 

The  internal  muscles  possess  less  irritability  than  the  exter- 
nal, depending  on  nervous  influence. 

Mechanical  irritation  is  much  more  efficacious  than  galvanic 
action  in  determining  their  contractions.  Galvanic  irritation 
acts  but  slightly  on  them  through  the  medium  of  the  nerves. 
Nevertheless,  the  cardiac  nerves  and  the  heart  being  compre- 
hended in  a  galvanic  circle,  the  continued  action  of  this  agent 
determines  movements  in  the  organ. 

The  irritability  or  susceptibility  of  contraction  of  the  inte- 
rior muscles,  is  the  more  remarkable,  from  its  being  materially 
excited  by  local  agents,  which  act  on  the  fibre  through  the 
medium  of  the  membrane  that  covers  it;  at  other  times  the 
cause  acts  by  sympathy:  thus  the  titillation  of  the  throat,  the 
presence  of  a  bougie  in  the  urethra,  of  a  suppository  in  the 
57 


440  GENERAL  ANATOMY. 

anus,  induce  the  action  of  the  stomach,  the  bladder,  and  the 
intestines.  The  will  has  little  control  over  the  contractility 
of  these  muscles;  yet  the  czsophagus,  the  rectum,  the  bladder, 
and  even  the  stomach  are  not  altogether  independent  of  it;  it 
appears  even  that  the  uterus,  at  least  in  birds,  is  also  some- 
times subject  to  the  will.  The  small  intestine,  on  the  con- 
trary, is  not  at  all  under  its  control ;  the  heart  is  equally  in- 
dependent of  it.  And  yet  the  case  is  still  cited  of  an  English 
captain,  reported  by  Dr.  Cheyne,  and  since  related  by  all 
physiologists,  and  that  of  the  late  Dr.  Bayle,  reported  by  M. 
Ribes,  who  could  at  pleasure  slacken  or  suspend  the  move- 
ments of  the  heart.  But  if  the  interior  muscles  are  not  sub- 
ject to  the  ordinary  influencegof  the  will,  the  strong  affections 
of  the  soul,  and  lively  emotions  of  the  mind,  influence  them  in 
the  most  evident  manner. 

Haller,  in  admitting  that  muscular  power  is  inherent  in  the 
muscles,  and  that  nervous  action  is  only  the  exciting  cause  of 
it,  was  led  to  admit,  and  most  of  his  successors  have  admitted 
still  more  positively  than  himself,  that  the  interior  muscles 
are  independent  of  the  nervous  action,  at  least  in  their  ordina- 
ry and  regular  movements.  The  experiments  of  Legallois 
afterwards  induced  the  admission  of  a  directly  contrary  opin- 
ion. The  more  recent  experiments  of  M.  Cliff,*  and  those  of 
M.  Wilson  Philip,!  and  the  comparative  observation  of  other 
animals,  of  monstrous  embryos  and  foetuses,  were  calculated  to 
modify  both  these  conclusions.  Known  facts  demonstrate,  in 
effect,  that  the  interior  muscles  are  independent  of  the  nervous 
spinal  marrow,  in  animals  and  monstrous  foetuses  which  have 
none,  as  well  as  in  embryos  which  as  yet  have  acquired  none; 
little  dependent  on  it  in  young  animals  in  which  its  influence 
is  not  of  long  standing,  and  in  animals  of  an  inferior  order,  in 
which  the  nervous  action  has  not  a  well  determined  centre; 
but  are,  on  the  contrary,  dependent  on  that  organ  in  the  adult 
man;  they  are  moreover  greatly  influenced  by  its  lesions,  and 
still  more  so  by  sudden  lesions  than  by  slow  alterations. 

*  Philos.  trans.  Ann.  1815. 

\Anexptr.  Ing.  into  the  laws  of  the  vital  functions,  &c.  Loml.  1818. 


OF  THE  EXTERIOR  MTJSC,L  441 

§  707.  When  the  interior  muscles  contract,  they  sometimes 
draw  into  simultaneous  and  associated  action  all  the  exterior 
muscles  which  can  contrihute  to  the  accomplishment  of  their 
function:  thus  in  coughing,  sneezing,  vomiting,  defecation,  ac- 
couchement, &c.,  a  number  more  or  less  considerable  of  mus- 
cles of  the  skeleton  act  by  association,  with'  interior  muscles. 
The  interior  muscles  have  no  real  antagonists  like  the  exte- 
rior muscles,  all  their  fibres  tending  to  one  sole  and  common 
end,  the  diminution  of  capacity  of  the  cavity  which  they  form. 
However,  we  may  consider  as  such,  1st,  the  foreign  substances 
thai;  keep  asunder  the  parietes  of  the  organs  formed  by  these 
muscles;  2d,  the  various  parts  of  a  particular  hollow  organ: 
for  example,  the  auricles  with  relation  to  the  ventricles;  the 
body  of  the  uterus,  and  that  of  the  bladder  with  respect  to  the 
neck  or  orifice  of  these  organs  ;  3d,  the  two  muscular  layers  in 
the  alimentary  canal  in  the  peristaltic  motion  ;  the  contraction 
of  the  longitudinal  fibres  determining,  by  pushing  forward  the 
faeces,  the  extension  of  the  annular  fibres.     Now,  there  hap- 
pens in  this  precisely  what  takes  place  in  all  antagonism:  the 
contraction  of  one  muscle  coincides  with  the  relaxation  of  its 
antagonist,  and  vice  versa;  4th,  finally,  the  interior  muscles 
find  antagonists  in  the  exterior  muscles.     These  muscles  have 
no  determined  fixed  point:  those  which  are  annular,  contract 
on  themselves;  those  which  are  longitudinal,  however,  have 
this  point  in  the  orifices  of  the  alimentary  canal;  those  of  the 
reservoirs,  as  the  bladder  and  uterus,  as  well  as  those  of  the 
heart,  have  also  a  fixed  point,  better  determined,  in  the  orifice 
of  these  organs. 


SECTION  III. 

OP  THE  EXTERIOR    MUSCLES. 

§  708.  These  muscles  are  also  called  voluntary  muscles,  mus- 
cles of  animal  functions,  of  animal  life,  muscles  properly  so 
called.  It  is  these  that  constitute  the  greater  part  of  the  mass 
of  the  body. 


442  GENERAL  ANATOMY. 

§  709.  They  are  very  numerous;  there  are  from  three  to  four 
hundred  of  them,  but  this  number  has  been  variously  stated. 
Some  regarding  as  several  muscles  what  others  have  repre- 
sented as  bundles  of  an  individual  muscle. 

§710.  Each  muscle  has  its  proper  name,  but  this  nomen- 
clature has  greatly  varied.  There  is  scarcely  a  single  muscle 
which  has  not  received  more  than  one,  name,  some  have  re- 
ceived as  many  as  a  dozen. 

The  denomination  of  the  muscles  has  been  derived  from 
several  considerations:  numerical  order  has  been  applied  to 
them,  thus  when  several  muscles  belong  to  the  same  part,  the 
same  region,  or  same  action,  &c.;  they  have  been  distinguished 
by  the  names  of  numbers,  as  the  radial,  the  adductor,  the  inter- 
osseous  muscles,  have  been  distinguished  by  first,  second,  &c. 
Before  James  Sylvius,  almost  all  the  muscles  were  thus  dis- 
tinguished by  the  name  of  numbers.  Some  have  adopted  as  sur- 
names, their  anterior,  posterior,  superior,  inferior,  superficial, 
deep-seated,  &c.,  situation,  or  they  have  been  distinguished  by 
the  name  of  the  part  they  move,  or  the  region  they  occupy,  as 
the  palpebral,  occular,  labial,  pectoral,  dorsal,  abdominal,  crural 
muscles,  &c.  Others  are  distinguished,  according  to  their  ex- 
tent, or  their  volume,  by  the  epithets  great,small, mean,  slender, 
vast,  wide,  long,  short,  &c.  Others  have  been  named  rhom- 
boidal,  square,  triangular,  scalenus,  &c.,  in  conformity  with 
the  figure  it  was  imagined  they  possessed;  or  else  they  have 
been  called  splenius,  by  being  compared  with  the  spleen,  or  a 
compress,  solearis  because  of  their  resemblance  to  the  fish 
called  a  sole,  or  to  the  sole  of  a  shoe.  Certain  muscles  have 
been  named  with  reference  to  their  direction,  right,  oblique, 
transversal,  spiral;  after  their  texture  and  their  composition, 
they  have  been  named  biceps,  triceps,  complexus  semi-ten- 
dinosus,  perforans,  perforatus,  &c.  Other  muscles  have  been 
denominated  according  to  their  insertions,  either  from  one  of 
them  only,  as  the  pterygoidi,  peronei,  zygomatici,  &c. ;  or  from 
two,  as  the  stylo-hyoideus,  sterno-hyoideus;  or  from  a  greater 
number,  as  the  sterno-cleido-mastoideus.  Others  again  have 
been  named  according  to  their  use,  flexors,  extensors,  eleva- 
tors, abductors,  depressors,  pronatores,  supinatores,  &c.;  finally, 


OF  THE  EXTERIOR  MUSCLES.  443 

even  these  are  not  all  the  considerations  on  which  the  nomen- 
clature of  the  muscles  is  based. 

Scarcely  any  of  these  considerations  are  absolutely  useless  to 
the  knowledge  of  the  functions  of  the  muscles;  nevertheless, 
the  most  useful  are,  without  doubt,  the  movement  itself,  the 
insertions,  the  region  occupied  by  the  muscle,  its  direction, 
&c.  It  would  matter  but  little  how  numerous  these  bases 
were,  provided  they  always  furnished  names  that  were  proper, 
distinct  and  short,  even  though  not  very  significative;  but 
almost  all  the  names  of  the  muscles  are  names  composed  of 
several  of  the  circumstances  indicated.  Thus  we  find  in  the 
muscular  nomenclature,  the  names  obliquus  externus  abdomi- 
nis,  rectus  anticus  capitis  longus,  radialis  externus  primus, 
rectus  femoris  anticus,  interosseus  dorsalis  manus  primus,  &c. 
This  inconvenience,  joined  to  that  resulting  from  the  multi- 
tude of  different  names  given  by  various  anatomists  to  the 
same  muscle,  induced  M.  Chaussier*  to  propose  a  reform  in 
anatomical  language,  and  especially  in  that  of  myology.  This 
reform  in  the  names  of  the  muscles  consisted  in  giving  to  each 
of  them  a  name  which  expresses  solely  and  constantly  the  two 
opposite  points  of  attachment,  designated  commonly  under 
the  names  of  origin  and  of  insertion;  but  the  able  author  of 
this  project  found  it  impossible  to  give  names  which  were  not 
at  the  same  time,  a  pretty  large  number  of  them  at  least,  com- 
posed of  some  others  of  the  circumstances  indicated  above. 
M.  Dumast  endeavoured  to  modify  the  nomenclature  of  M. 
Chaussier  by  indicating  in  his  names  all  the  points  of  attach- 
ment of  the  muscles.  M.  Dumeril,:j:  also  engaged  in  the  re- 
form of  the  anatomical  language,  by  taking  for  the  root  of  this 
language  the  Greek  or  Latin  names  of  the  bones  and  of  the 
viscera,  and  by  merely  varying  the  termination  of  these  names 
for  the  varipus  other  organs  and  for  the  regions.  The  termina- 
tion of  the  muscles  was  ien  ;  thus  the  name  occipito  frontien, 

*  Exposition  sommaire  des  muscles  du  corps  humain.  Dijon.,  1789. — Ta- 
bleau des  muscles  de  fhomme.  Paris,  1797. 

f  Systeme  mtfhodique  de  nomenclature  et  de  c lass i-ficat ion  des  muscles  du 
corps  humain,  etc.  Montpillier,  1797,  in  4to. 

j  Magasin  Emydoptdique. 


444  GENERAL  ANATOMY. 

without  joining  to  it  the  word  muscle,  designates  in  this 
nomenclature,  the  occipito  frontalis.  Vicq.  d'Azyr  had 
equally  directed  his  views  to  the  necessity  of  reforming  the 
anatomical  language;  he  did  not  execute  his  project.  Doctor 
Barclay  also  engaged  in  this  object,  and  directed  his  special 
attention  to  giving  proper  and  precise  names  to  the  different 
regions  of  the  body.  M.  Schreger*  has  collected  together 
most  of  the  anatomical  names  employed  up  to  his  time,  in  a 
voluminous  synonymy,  where  is  found  almost  as  many  names 
to  some  organs,  as  there  are  treatises  on  anatomy.  The  fear 
of  contributing  to  the  confusion,  which  is  augmented  almost 
every  time  that  a  new  treaty  makes  its  appearance,  ought  to 
induce  the  anatomists  to  make  use  of  names  already  in  use,  in 
choosing  from  among  them  those  that  are  best  known,  the 
most  simple  and  the  most  significant. 

§  711.  According  to  their  situation  and  their  destination  to 
move  any  particular  part,  the  exterior  muscles  are  distin- 
guished by  those  of  the  skeleton  and  the  bones,  by  those  of 
the  larynx,  and  by  those  of  the  organs  of  the  senses  and  the 
skin;  several  exterior  muscles  belong  also  to  the  orifices  of 
the  digestive,  respiratory,  genital  and  urinarypassages,  and 
are  there  insensibly  confounded  with  the  interior  muscles. 

The  muscles  of  the  skeleton  are  situated  in  the  trunk  and 
in  the  members:  in  the  members  they  form  considerable 
masses,  and  are  elongated;  in -the  trunk  they  are  broad,  nu- 
merous in  the  back  and  the  abdomen,  less  so  in  the  thorax, 
and  still  less  so  about  the  cranium. 

§  712.  The  muscles  vary  greatly  in  volume,  some  are  great 
or  voluminous,  others  are  moderate  in  size,  others  small,  and 
others  again  very  small. 

§  713.  All  the  muscles  are  in  pairs,  except  the  diaphragm, 
the  sphincters  of  the  mouth  and  anus,  the  arytjienoidasus, 
and  often  the  levator  uvulae;  all,  except  the  diaphragm,  are 
symmetrical,  or  similar  on  both  sides,  with  the  slight  differ- 
ence ordinarily  observable  in  the  volume  of  the  two  lateral 
sides  of  the  body. 

*  Synonyjala  anaiomica,  aud.  Chr.  II.  Th.  Schreger.     Furthii,  180.  . 
8vo.  380  pages. 


OP  THE  EXTERIOR  MUSCLES. 

According  to  their  form  the  muscles  are  moreover  distin- 
guished by  the  terms  broad,  long  and  short. 

The  broad  muscles  belong  to  the  trunk;  some  of  them  ex- 
tend from  the  trunk  to  the  members,  and  are  then  elongated 
in  this  last  part  of  their  extent. 

The  long  muscles  appertain  to  the  members,  and  are  in  ge- 
neral disposed  in  layers,  the  most  exterior  being  the  longest 
and  the  straightest,  the  more  profound  being  much  shorter 
and  more  oblique:  a  disposition  important  to  be  known  in  the 
practice  of  amputations,  since  the  muscles,  unequal  in  length, 
must  contract  unequally. 

The  short  muscles  are  met  with  in  the  trunk  and  in  the 
members,  near  the  articulations. 

§  714.  The  direction  of  the  muscles  is  that  of  a  line  ex- 
tended, passing  through  their  centre,  from  one  extremity  to 
the  other;  it  is  often  very  different  from  that  of  its  fibres,  and 
this  last  is  the  most  important  circumstance.  When  all  the 
fibres  are  straight  and  parallel  to  each  other,  the  power  of  the 
muscle,  which  is  equal  to  the  sum  of  the  power  of  all  the 
fibres,  operates  in  a  manner  parallel  to  the  direction  of  these 
fibres.  But  if  the  fibres  are  oblique  with  respect  to  each 
other,  the  intensity  and  the  direction  of  the  power  will  be 
different. 

§  715.  In  general  there  is  perceived  in  each  muscle  a  body 
or  belly,  and  two  extremities,  the  one  of  origin,  the  other  of 
insertion.  The  body  is  the  fleshy  part,  the  extremities  are 
ordinarily  tendinous:  the  extremities  are  also  frequently  dis- 
tinguished into  point  of  origin,  of  adhesion  or  stationary  point, 
and  in  moveable  point  or  of  insertion;  but  many  of  the  mus- 
cles will  not  accommodate  themselves  to  this  description. 
Those  to  which  it  would  best  apply  are  certain  muscles  of  the 
members,  which  are  elongated,  swelled  in  the  middle,  because 
of  the  disposition  of  their  fleshy  fibres;  formed  of  a  short  ten- 
don at  their  superior  extremity,  generally  the  most  fixed,  and 
of  a  long  tendon  at  the  other  extremity,  generally  the  most 
moveable.  But  in  these  muscles,  the  movement  may  be  divid- 
ed between  the  two  points,  and  sometimes  may  even  be  en- 
tirely executed  by  the  point  most  elevated. 


446  GENERAL  ANATOMY. 

§  716.  Certain  muscles  form  one  sole  fleshy  body  between 
the  two  attachments;  others,  on  the  contrary,  are  formed  of 
very  distinct  bundles,  which  might  be  taken  for  so  many  mus- 
cles; such,  in  particular,  are  the  masseter,  the  deltoid,  the  sub- 
scapulary,  the  glutseus  muximus,  &c. 

§  717.  There  are  muscles  which  in  their  whole  extent  re- 
main simple  and  distinct,  and  others  which  are  divided  into 
several  parts,  or  confounded  with  others  at  one  of  their  extre- 
mities: thus,  some  mu'scles,  simple  at  their  insertion,  are  se- 
parated, at  their  origin,  into  two  or  three  parts:  such  are  the 
biceps  and  the  triceps;  such  are  also  the  sterno-mastoideus  and 
the  pectoralis  major,  which  for  this  reason  some  authors  have 
considered  as  composed  of  two  muscles  each;  thus  the  com- 
mon extensor  and  flexor  muscles  of  the  fingers  and  toes,  though 
simple  at  their  origin,  are  divided  at  their  insertion  into  seve- 
ral parts.  The  serrati  transversi  and  other  muscles  which  are 
attached  to  the  ribs  by  digitations,  are  also  nearly  in  the  same 
state.  The  muscles  which  have  a  common  origin  may  be 
compared  to  those  of  this  description,  as  the  muscles  that  are 
attached  to  the  ischium,  as  well  as  those  with  a  common  inser- 
tion, as  the  latissimus  dorsi  and  the  teres  major. 

§  718.  There  are  again  muscles  the  composition  of  which  is 
different:  such  are  several  of  the  spinal  or  vertebral  muscles, 
and  particularly  the  transversalis  spinse,  the  longissimus  dorsi, 
and  sacro  lumbalis;  they  each  result  from  many  muscular 
bundles,  distinct  at  the  extremities  and  confounded  at  the  cen- 
tre, in  such  a  manner  that  each  portion  of  muscle,  though  sin- 
gle at  one  extremity,  terminates  at  the  other  with  two  parts; 
and  reciprocally  each  of  the  latter  is  attached  to  a  double  por- 
tion of  the  opposite  extremity:  these  muscular  bundles  suc- 
ceeding each  other,  and  uniting  with  each  other  laterally,  there 
results  from  it  a  very  long  muscle,  composed  of  short  bundles, 
distinct  at  their  extremities,  and  united  laterally  in  their  mean 
part.  Each  bundle  being  closely  united  with  the  two  bundles, 
can  not  contract  without  the  latter  entering  into  action  at  the 
same  time,  so  that  the  movement  is  always  communicated  at 
once  to  several  vertebrae  or  ribs:  a  disposition  altogether  in 


OP  THE  EXTERIOR  MUSCLES.  447 

conformity  with  that  of  the  hones,  which  are  always  to  be 
moved,  several  of  them  simultaneously. 

§  719.  The  muscles  of  the  skeleton,  and  these  are  the  most 
numerous,  have  their  two  extremities  attached  to  the  perioste- 
um and  to  the  surface  of  the  bones  by  tendons  or  aponeuroses. 
The  muscles  of  the  larynx  are  attached  in  the  same  manner, 
to  the  cartilages  and  perichondrium.  The  muscles  which  ex- 
tend from  the  skeleton  to  the  organs  of  sense,  and  are  inserted 
into  cartilages,  are  besides  provided  with  tendons  at  both  ex- 
tremities ;  those  which  are  attached  to  the  teguments  are,  on 
the  contrary,  destitute  of  tendons  at  their  insertion  in  the  der- 
mis. 

Besides  the  tendons  and  aponeuroses  of  attachment  which 
are  found  at  the  extremities  of  most  of  the  muscles,  some  of 
them  also  present  tendons  or  aponeuroses  of  intersection,  which 
occupy  some  point  of  their  extent,  and  divide  them  into  seve- 
ral fleshy  bodies.  Of  this  description  are  the  maxillar  digas- 
tric and  cervical  digastric  muscles,  which  are  divided,  by  ten- 
dons, into  two  very  distinct  bodies;  such  are  also  the  sterno- 
hyoideus,  scapulo-hyoideus,  the  rectus  abdominis,  &c.  the 
fleshy  body  of  which  is  divided  by  aponeuroses. 

§  720.  In  a  great  many  of  the  muscles  the  fibres  are  straight, 
and  obviously  parallel  from  one  end  to  the  other.  In  several 
muscles,  the  fleshy  fibres,  all  parallel,  extend  obliquely  be- 
tween two  aponeurotic  tendons  expanded  on  two  opposite 
faces  of  the  fleshy  body;  such  is  the  cruralis  anticus.  It  was 
muscles  of  this  description,  without  doubt,  that  induced  Gas- 
sendi  to  compare  the  muscles  generally  to  a  tackle  of  pullies. 
Other  muscles  are  radiated,  as  the  great  pectoralis  major,  and 
the  latissimus  dorsi,  the  fibres  of  which,  while  spread  at  their 
origin,  are  collected  into  a  thick  bundle  towards  their  inser- 
tion; as  the  glutaeus  medius,  and  glutaeus  minimus,  whose 
fibres  terminate  successively  on  an  aponeurotic  expansion. 
In  others,  the  fibres  are  extended  thus  obliquely  from  their 
origin  from  a  bone  to  the  side  of  a  tendon:  these  muscles  are 
called  semi-pennate;  of  this  description  are  the  peronae. 
Others  are  pennated,  the  fibres  passing  obliquely  on  the  two 
sides  of  a  tendon;  in  some  others,  very  analogous  to  these 
5S 


GENERAL  ANATOMY. 

last,  the  fibres  form  two  planes,  which  are  inserted  on  the  two 
faces  of  a  middle  aponeurosis;  such  as  the  temporal  muscle. 
Other  muscles  are  still  more  compound,  as  the  deltoid,  the 
masseter,  &c.  which  result  from  the  union  of  several  penni- 
form  bundles. 

§721.  The  texture  of  the  exterior  muscles  always  results 
from  bundles  more  or  less  distinct,  which  generally  terminate 
at  both  ends  on  tendinous  tissue;  these  bundles  are  composed 
of  visible  fasciculi  or  fibres,  themselves  resulting  from  micro- 
scopic elementary  fibres.  The  cellular  tissue  and  the  adipose 
tissue  form  for  them  envelopes  and  partitions  the  more  dis- 
tinct in  proportion  as  the  bundles  are  themselves  distinct  and 
voluminous.  The  nerves  of  these  muscles  are  very  abundant, 
especially  in  those  of  the  organs  of  sense,  and  almost  all  come 
from  the  spinal  marrow;  few  are  derived  from  the  grand  sym- 
pathetic, and  these  last  are  never  alone. 

§  722.  Besides  these  parts  so  essential  to  the  muscles,  these 
organs  have  dependences:  these  are  the  fasciae  (519,)  or  en- 
veloping aponeuroses  which  surround  the  muscles,  maintain 
them  in  their  place,  and  furnish  them  with  partitions  by  which 
they  are  separated,  as  well  as  points  of  attachment;  it  is  also 
the  sheaths  and  rings  that  enclose  the  tendons  and  prevent 
their  being  displaced,  and  the  synovial  membranes  that  facili- 
tate their  sliding. 

§723.  The  muscles  are  divided,  with  reference  to  the  mo- 
tions which  they  produce,  into  congenerous  and  antagonist 
muscles,  according  as  they  concur  in  the  same  movements,  or 
produce  opposite  ones.  The  motions  which  take  place  in 
the  human  body,  and  which  are  produced  by  the  muscles,  are 
movements  of  flexion  and  of  extension,  of  lateral  inclination, 
of  rotation  in  two  opposite  directions,  which  in  the  forearm 
is  distinguished  by  the  terms  pronation  and  supination,  of  ele- 
vation and  depression,  of  adduction,  abduction,  and  deduction, 
of  dilation  and  constriction,  of  protraction  and  retraction,  &c. 
From  these  motions  the  muscles  are  called  flexors,  extensors, 
pronators,  supinators,  elevators,  &c. 

The  antagonist  muscles  present  some  differences:  in  almost 
all  parts  of  the  body,  the  muscles  destined  to  effect  a  motion, 


OF  THE  EXTERIOR  ?>P  449 

are  stronger  than  those  which  produce  the  opposite  motion. 
Those  of  the  two  sides  of  the  body  which  produce  the  lateral 
inclination,  and  the  rotation  round  the  axis  of  the  body,  pre- 
sent only  the  slight  difference  which  is  generally  observable 
between  the  two  sides  of  the  body.  The  others  present  much 
more  important  differences.  Borelli  thought  that  the  flexors 
were  shorter  than  the  extensors,  and  that  contracting  with  an 
equal  force,  they  necessarily  draw  the  bones  in  flexion. 
Richerand  also  thinks  that  the  difference  is  in  favour  of  the 
former;  Meckel  has  adopted  this  opinion:  these  two  physiolo- 
gists are  of  opinion  that  this  difference  is  established  on  the 
observation  of  the  bent  attitude  that  is  assumed  by  every  part 
of  the  body  in  a  state  of  repose,  and  that  its  cause  exists  in  the 
force  and  length  of  the  muscles,  in  the  volume  of  their  nerves, 
and  in  the  more  favourable  disposition  of  the  flexors,  relatively 
to  the  centre  of  motion,  and  to  the  direction  of  the  bones. 

Ritter  has  added  to  these  differences  that  the  flexors  contract 
when  the  positive  pole  of  the  galvanic  pile  communicates  with 
the  muscular  extremity  of  the  nerve,  and  the  negative  pole 
with  the  central  extremity;  and  that  the  contrary  obtains  with 
the  extensor  muscles.  This  difference,  doubtless,  is  a  mere 
difference  of  galvanic  susceptibility ;  a  susceptibility  sufficiently 
powerful  in  the  strongest  muscles,  to  cause  them  to  contract 
under  the  least  favourable  circumstance  of  the  galvanic  action. 

Roulin*  thinks  with  Borelli,  that  the  principal  cause  of  an- 
tagonism between  the  flexors  and  extensors  depends  on  their 
respective  length,  and  consequently  on  their  tension. 

This  question  perhaps  merits  being  considered  in  a  more 
general  manner;  the  predominance  must  be  sought  in  the 
length  and  in  the  volume  of  the  muscles,  and  more  properly 
in  the  number  of  fleshy  fibres  that  enter  into  their  composi- 
tion- it  must  also  be  sought  in  the  disposition  of  the  muscles 
relatively  to  the  levers  on  which  they  act ;  it  is  necessary  to 
observe  what  the  attitude  is  that  the  parts  take  in  their  most 
ordinary  action,  and  that  which  they  take  in  repose,  during 

*  See  Recherches  sur  fa  mouvemens  et  ks  attitudes  de  thomme,  dans  k 
journal  de  physiologic,  Vol.  I.  et  II. 


450  GENERAL  ANATOMY. 

sleep,  and  in  a  state  of  paralyses;  regard  must  also  be  had  to 
that  which  they  take  in  general  tonic  spasm  or  in  tetanus: 
now,  in  having  regard  to  these  various  considerations,  it  would 
seem  that  the  extensors  are  the  preponderating  muscles  in 
the  trunk;  in  the  jaw,  the  elevators;  in  the  superior  members 
generally,  the  flexors;  in  the  forearm,  the  pronators;  in  the 
inferior  members  generally,  the  extensors;  and  in  the  feet,  the 
adductors. 

§  724.  There  are  in  the  organization  several  circumstances* 
unfavourable  to  the  action  of  the  muscles,  and  which  diminish 
their  power  of  contraction  or  effective  force  to  an  efficacious 
force,  i.  e.  to  a  much  less  considerable  result.  These. circum- 
stances, well  ascertained  since  Borelli,  are,  1st,  the  equal  divi- 
sion of  muscular  effort  between  its  two  attachments,  whilst  one 
point  alone  in  general  is  to  be  moved ;  2d,  the  unfavourable 
lever,  that  of  the  third  kind,  by  which  a  great  part  of  the 
power  is  lost;  3d,  the  oblique  insertion  of  the  muscles  on  the 
bones,  and  of  the  fleshy  fibres  on  the  tendons ;  4th,  the  resist- 
ance of  the  antagonist  muscles  ;  5th,  the  friction  of  the  ten- 
dons and  that  of  the  articulations. 

There  are  also  in  the  organization,  circumstances  which,  by 
favouring  muscular  action,  diminishes  the  influence  of  the 
former:  of  this  description  are  the  change  of  the  angle  which 
the  muscles  and  the  bone  form,  by  means  of  certain  anatomical 
dispositions,  as  the  volume  of  the  articular  extremities  of  the 
bones,  the  existence  of  the  apophyses  at  the  place  where  the 
muscles  are  attached,  that  of  the  sesamoid  bones,  &c.  Such  is 
also  the  diminution  of  friction  by  the  synovia,  &c. 

Finally,  the  animal  mechanism  presents  the  same  perfection 
as  that  which  is  every  where  to  be  admired  in  nature.  What 
the  muscle  loses  in  force,  motion  gains  in  extent  and  rapidity, 
by  the  employment  of  the  lever  of  the  third  kind,  and  by  the 
obliquity  of  insertion.  On  the  other  hand,  the  obliquity  of  the 
muscular  fibres  upon  the  tendons,  by  diminishing  the  extent 
of  motion,  and  even  the  force  of  the  muscle,  permits,  under  a 
small  volume,  the  union  of  a  very  great  number  of  fibres, 

*  J.  Alph.  Borelli,  de  motu  animalium,  opus  posthumum. 


OF  THE  EXTERIOR  MUSCLES.  451 

which  compensates,  and  much  more  than  compensates,  the  loss 
of  power;  without  mentioning  the  form  and  freedom  of  the 
limbs,  which  could  not  take  place  with  any  other  insertion, 
or  any  other  direction  of  the  muscles  with  relation  to  the 
bones. 

§  725.  The  muscle  is  the  seat  and  the  immediate  organ  of 
contraction,  just  as  the  teguments  and  the  organs  of  sense, 
which  form  part  of  them,  are  the  seat  of  impression.  But  just 
as  sensation  takes  place  only,  in  so  far  as  the  impression  is 
propagated  by  the  nerves  to  the  nervous  centre,  so  is  it  from 
the  nervous  centre  that  volition  is  propagated,  by  the  nerves, 
to  the  muscle,  for  setting  it  in  motion.  In  both  cases,  there 
is,  moreover,  something  that  is  entirely  incomprehensible;  this 
is,  the  manner  in  which  the  being,  the  self,  (moi)  acquires  the 
knowledge  of  the  sensation,  and  also  the  manner  in  which  it 
determines  the  volition.  This  is  not  the  proper  place  for  exa- 
mining the  yet  unsolved  question  of  the  reciprocal  action  of 
the  organism  and  the  self  (moi}. 

Be  this  as  it  may,  the  volition  proceeds  from  the  nervous 
centre,  is  propagated  by  the  nerves,  and  self  induces  the  con- 
traction of  the  external  muscles.  If  the  nerve  be  cut  or  inter- 
rupted by  a  tight  ligature,  &c.  the  muscle,  still  irritable,  no 
longer  contracts  voluntarily.  In  the  following  chapter  will 
be  seen  what  is  the  precise,  or,  at  least,  probable,  seat,  in  the 
nervous  system,  of  the  organic  principle  of  the  voluntary 
motions. 

§  726.  The  effects  of  the  contraction  of  the  exterior  muscles 
are  to  determine  the  attitudes  and  motions  of  the  body,  by 
acting  upon  the  skeleton ;  to  move  the  skin  and  organs  of 
sense;  to  produce  the  voice,  speech,  and  gesture;  and,  lastly, 
to  subserve,  in  a  more  or  less  necessary,  but  always  auxiliary, 
manner,  the  vegetative  functions. 

§  727.  It  has  already  been  seen  that  the  straight  muscles,  in 
contracting,  draw  one  of  their  extremities,  or  both,  nearer  to 
the  centre,  according  as  one  of  the  points  of  attachment  only 
is  moveable,  or  as  they  are  both  so;  and  that  the  circular  mus- 
cles, in  contracting,  narrow  the  orifices  or  canals  which  they 
form.  The  curved  muscles  become  straight  when  they  con- 


452  GENERAL  ANATOMY. 

tract,  if  their  attachments  are  fixed;  and,  in  tending  to  bcrome 
so,  they  diminish  the  cavities  of  which  they  form  the  walk: 
as  is  the  case  with  the  abdominal  muscles  and  diaphragm  with 
respect  to  the  abdomen;  and  they  enlarge  the  cavity  to  which 
they  correspond  by  their  convex  surface;  as  the  diaphragm 
does  with  respect  to  the  thorax.  The  reflected  muscles,  and 
they  are  very  numerous,  tend,  like  the  curved  muscles,  to 
become  straight  during  their  contraction;  but  if  any  insur- 
mountable obstacle  comes  in  the  way,  the  motion,  the  direc- 
tion of  which  is  changed,  is  transmitted  to  the  one  or  the  other 
extremity,  or  to  both,  according  to  their  mobility. 

§  728.  When  one  of  the  parts  to  which  a  muscle  is  attached, 
is  immoveable,  the  other  capable  of  being  moved,  it  draws 
the  latter  towards  the  former;  as  is  the  case  with  the  muscles 
which  extend  from  the  bones  to  the  soft  parts,  &c.  When  one 
of  the  two  parts  has  little  mobility,  and  the  other  is  very  mo- 
bile, as  the  trunk  with  reference  to  the  limbs,  the  central  ex- 
tremity of  the  limbs  with  reference  to  the  peripheric  extremi- 
ty, &c.  the  latter  is  in  general  the  only  one  that  moves.  But 
it  is  to  be  observed,  then,  in  this  case,  that  the  fixed  point,  and 
the  moveable  point  of  the  muscles  may  change.  Thus,  in 
the  most  ordinary  motions  of  the  arm,  the  muscles  which 
move  that  part  have  their  fixed  point  in  the  trunk,  and  their 
moveable  point  in  the  limb.  On  the  contrary,  in  the  action 
of  climbing  up  a  tree,  the  fixed  point,  at  the  moment  when 
the  trunk  rises  towards  the  arm  which  was  previously  fixed, 
is  in  the  arm,  and  the  moveable  point  in  the  trunk.  So  also 
in  the  action  of  going  up  a  ladder,  when  the  leg  is  carried 
forwards  and  upwards,  the  fixed  point  is  in  the  trunk.  When 
afterwards  the  trunk  rises  towards  the  leg  whose  foot  is  sta- 
tionary and  firm,  the  fixed  point  is  in  the  leg,  and  the  move- 
able  points  of  the  muscles  are  in  the  thigh  and  trunk. 

When  the  two  parts  to  which  the  muscles  are  attached  are 
nearly  equally  mobile,  contraction  tends  to  move  them  about 
equally.  Thus  when  one  is  lying  upon  a  horizontal  plane, 
the  contraction  of  the  anterior  muscles  of  the  trunk  tends 
nearly  equally  to  bend  the  head  upon  the  neck,  and  the  pelvis 
upon  the  loins. 


OF  THE  EXTERIOR  MUSCLES.  453 

In  this  case  and  in  the  preceding,  which  are  of  extremely 
frequent  occurrence  in  the  animal  mechanism,*  the  part  which 
is  to  serve  as  a  fixed  point  is  retained  by  the  contraction  of 
other  muscles  which  render  it  motionless.  The  motions  ap- 
parently the  most  simple  almost  always  require  the  simultane- 
ous action  of  a  greater  number  of  other  muscles  than  those 
which  are  destined  to  produce  them  immediately. 

§  729.  It  is  in  efforts  especially  that  we  observe  these  mus- 
cular synergies. 

An  effort, t  nisus,  is  any  muscular  action  of  extraordinary 
intensity,  destined  to  surmount  an  external  resistance,  or  to 
perform  a  laborious  function,  whether  accidentally  or  natural- 
ly. Thus,  the  action  of  raising  or  carrying  a  heavy  body, 
parturition,  difficulty  of  passing  the  urine,  &c.  require  efforts 
before  they  can  be  executed. 

In  every  effort,  there  is  an  extraordinary  nervous  influx 
upon  the  muscles.  Sometimes  this  influx  is  voluntary,  some- 
times involuntary.  In  the  latter  case,  it  is  irresistibly  deter- 
mined by  the  connexion  already  remarked  between  the  invo- 
luntary internal  muscles,  and  their  external  congenerous 
muscles.  In  every  effort,  also,  a  great  number  of  muscles, 
sometimes  the  whole  apparatus  of  motion  is  in  action.  Lastly, 
in  every  effort,  the  lungs  are  first  filled  with  air  by  an  inspira- 
tion, the  glottis  is  closed  or  simply  narrowed,  the  muscles  of 
expiration  are  contracted,  and  the  walls  of  the  thorax  are  thus 
rendered  immoveable,  in  order  to  present  fixed  points  of  at- 
tachment to  the  muscles  of  the  abdomen  and  limbs. 

The  effects  of  efforts  are  to  retard  or  prevent  the  entrance 
of  the  venous  blood  into  the  thoracic  trunks,  whence  its  re- 
flux and  its  stasis  in  the  veins  of  the  neck,  the  head,  the  abdo- 
men, and  even  the  limbs;  to  compress  the  thoracic  and  abdo- 

*  Winslcnv,  Mem.  de  PAcad.  des  Sc.,  1719-23-26-29-30-39-40,  &c. 

f  Js.  Bourdon,  Recherches  sur  le  mt-canisme  de  la  respiration  et  de  la  circu- 
lation du  sang.  Paris,  1820. — J.  Cloquet,  De  V influence,  des  efforts  sur  les 
organ cs  renfermcs  dans  la  cavite  thorachique.  Paris,  1820. — Magendie,  7> 
^influence  des  mouvemens  de  la  poitrine,  et  des  efforts,  sur  la  circulation  du 
sung.  Journal  de  Physiologic,  vol.  i. 


454  GENERAL  ANATOMY". 

minal  viscera,  and  even  sometimes  to  produce  their  expulsion, 
especially  that  of  the  latter,  through  an  opening  in  the  walls. 
Efforts  occasionally  even  go  so  far  as  to  produce  rupture  of 
the  muscles,  tendons  or  bones,  and  to  cause  ruptures  of  the 
blood-vessels,  hemorrhages  and  effusions  of  blood. 

§730.  The  muscles  which  pass  over  several  joints  may 
move  them  all.  Thus  the  flexors  of  the  fingers,  after  having 
bent  the  third  and  second  phalanges  on  the  first,  bend  the  lat- 
ter on  the  metacarpus,  and  the  hand  on  the  fore-arm.  One  of 
the  two  even  contributes  to  pronation.  It  is  the  same  in  the 
foot,  where  the  common  extensor  of  the  toes  bends  the  foot 
upon  the  leg,  and  where  even  the  same  disposition  occurs. 
These  muscles,  which  pass  over  several  joints,  have  also  other 
uses.  They  are  auxiliaries  or  supplementary  parts  to  shorter 
muscles,  extending  only  to  the  two  bones  united  by  an  articu- 
lation. Thus,  the  biceps,  semi-tendinosus  and  semi-membra- 
nosus  of  the  thigh,  which  pass  over  two  articulations  bending 
in  opposite  directions,  may  assist  or  become  the  substitute  in 
their  functions,  of  the  extensor  muscles  of  the  pelvis  upon  the 
thigh,  and  of  the  flexors  of  the  thigh  upon  the  leg.  The  mus- 
cles of  this  kind,  which  are  so  numerous  in  the  limbs,  espe- 
cially the  inferior  ones,  and  which  equally  exist  in  the  di- 
rection of  extension  and  in  that  of  flexion,  appear  also  to  be 
intended  for  the  purpose  of  rendering  the  act  of  standing  se- 
cure, by  applying  the  articular  surfaces  against  each  other, 
and  preventing  motion  in  all  directions. 

§  731.  Muscular  motion  is  simple  when  it  is  impressed  by 
a  single  muscle  or  by  several  muscles  which  act  in  the  same 
direction.  It  is  compound,  when  it  is  produced  by  several 
muscles  which  act  in  different  directions.  Simple  motion 
commonly  takes  place  in  the  direction  of  the  muscle  itself  or 
of  the  muscles  which  produce  it.  Thus  the  flexors  of  the  fingers 
bring  them  in  their  proper  direction.  In  other  cases,  the  mus- 
cle being  reflected,  the  direction  of  the  motion  is  determined 
by  that  of  the  portion  of  the  muscle  which  extends  from  the 
place  where  it  changes  its  direction  to  the  mobile  part.  Thus 
the  motion  induced  by  the  obliquus  occuli  longus,  by  the  cir- 
cumflexus  muscle  of  the  palate,  the  lateral  peronsei,  £c.,  has  a 


OF  THE  EXTERIOR  MUSCLES.  455 

direction  determined  by  that  of  the  last  portion  of  these  mus- 
cles. The  direction  of  the  motion  is  frequently  in  a  great 
measure  determined  by  that  of  the  articulations  of  the  bones. 
Thus  the  bones  articulated  by  ginglymus  and  by  rotatory  ar- 
ticulation, although  most  of  them  have  oblique  muscles,  move 
in  only  two  opposite  directions.  Thus,  on  the  other  hand, 
the  same  muscle,  the  biceps  flexor  cubiti,  without  changing  its 
direction,  produces  by  its  contraction  the  supination  and  flex- 
ion of  the  fore-arm.  Thus  also,  the  pyramidales,  gemelli,  &c., 
which  are  rotators  of  the  thigh  outwards,  when  it  is  extended, 
become  abductors  when  it  is  bent. 

§  732.  In  many  cases  the  muscular  motions  are  compound; 
several  muscles  contracting  simultaneously,  communicate  to  a 
moveable  part  a  motion  different  from  that  which  results  from 
the  contraction  of  each  of  them  in  particular.  Thus,  if  the 
rectus  superior  and  rectusexternus  of  the  eye  contract  toge- 
ther and  with  equal  force,  the  eye  obeying  these  different 
forces,  the  pupil  will  be  directed  upwards  and  outwards.  Thus, 
if  the  pectoralis  major,  which  carries  the  arm  inwards  and 
forwards,  contracts  at  the  same  time  with  the  latissimusdorsi, 
which  carries  it  inwards  and  backwards,  the  arm  will  be  car- 
ried, by  a  compound  motion,  directly  inwards.  The  motions 
of  the  shoulder  are  always  compound.  Many  other  parts  are 
often  so  also;  and  were  it  not  so,  the  motions,  which  are  so 
varied,  would  be  extremely  limited. 

§  733.  The  motions  of  the  voluntary  muscles  are  in  fact 
most  commonly  combined.  In  this  respect,  the  muscular  ac- 
tions may  be  distinguished  into  isolated  motions,  resulting 
from  a  single  muscle  in  contraction;  into  associated  or  com- 
bined motions,  resulting  from  the  action  of  several  associated 
muscles,  whether  congenerous  or  antagonist,  to  produce  deter- 
minate motions,  as  those  of  flexion,  extension,  &c. ;  into  co- 
ordinate motions,  as  those  which  by  their  association  produce 
standing,  locomotion,  &c.;  lastly,  actions  of  the  will,  or  mus- 
cular actions  directed  by  volition.  These  variations  in  mus- 
cular action  depend  upon  the  nervous  influence,  according  as 
it  is  voluntary,  and  according  as,  without  the  influence  of  the 

will,  it  is  determined  by  irritation  of  the  nervous  centre,  by 
5!) 


456  GENERAL  ANATOMY. 

that  of  the  plexus  of  a  limb,  or  only  by  that  of  an  isolated 
nerve. 

§  734.  The  contraction  of  the  external  muscles,  through 
causes  which  act  upon  the  muscular  tissue,  or  upon  the  nerves, 
or  upon  the  nervous  centre,  sometimes  becomes  feeble  and  un- 
certain (in  trembling;)  impossible  (in  paralysis;)  permanent 
(in  tonic  spasm  or  contraction,  tetanus;)  involuntary  and  irre- 
gular (in  convulsions,  clonic  spasm,  or  contraction.) 


OP  THE  NERVOUS  SYSTEM. 


CHAPTER  X. 


OF  THE  NERVOUS  SYSTEM. 

§  735.  The  Nervous  System,  Systema  nerveum,  compre- 
hends cords  (nerves,)  enlargements  (ganglia,)  and  a  central 
mass  (the  brain  in  general,)  formed  of  a  white  and  grayish 
substance,  which,  during  life,  keeps  up  the  irritability,  are  the 
conductors  and  receptacle  of  the  sensations,  the  point  of  de- 
parture and  the  conductors  of  volition;  in  a  word,  the  organs 
of  innervation. 

The  nervous  centre  is  moreover  the  organ,  or  in  other  words 
the  material  instrument  of  intellect. 

§  736.  The  Asclepiades  were  not  acquainted  with  either  the 
nerves  or  the  ganglia.  One  may  easily  be  convinced,  on  read- 
ing the  works  of  Hippocrates  and  Aristotle,  that  they  have 
confounded  under  the  nameN^w,  ligaments,  tendons,  nerves, 
and  even  the  vessels.  Praxagoras  appears  to  have  been  the 
first  who  had  any  correct  idea  of  difference  among  the  white 
organs;  but  having  placed  the  origin  of  the  nerves  at  the  ter- 
mination of  the  arteries,  he  gave  rise  to  an  opinion  respecting 
the  hollow  structure  of  the  nerves,  which  has  been  continued 
up  to  the  present  time.  Herophilus  and  Erasistratus  knew 
the  connexion  of  the  nerves  with  the  brain,  but  they  continu- 
ed to  give  the  same  name  to  the  tendons  and  ligaments.  Ga- 
len unraveled  the  confusion  which  still  prevailed  in  his  time 
with  regard  to  this  subject,  by  giving  names  to  the  ligaments 
and  tendons.  By  perceiving  that  the  nerves  are  medullary  in 
their  interior,  and  membranous  at  the  exterior,  he  clearly  de- 
termined their  connection  with  the  spinal  marrow  and  brain. 
He  remarked,  in  opposition  to  an  opinion  that  had  existed  pre- 
viously to  him,  that  the  spinal  marrow  is  subordinate  to  the 


ti  T :  N  E  R  A  L   A  X  A  T  0  M  Y .- 


brain,  which  is  therefore  the  nervous  centre.  Me  attempted 
to  establish  a  distinction  between  the  nerves  of  feeling  and 
those  of  motion,  and  first  described  and  named  the  nervous 
ganglia.  He  had  also  made  considerable  progress  in  the  know- 
ledge of  the  nerves  in  particular.  The  anatomists  of  the  Ita- 
lian school  having  found  neurology  much  in  the  state  to  which 
Galen  had  brought  it,  greatly  improved  its  condition.  G. 
Bartholin  reproduced  the  opinion  of  Praxagoras  and  some 
others  of  the  ancients,  that  the  spinal  marrow  is  the  centre  of 
the  nervous  system,  and  that  the  brain  is  only  a  continuation 
of  it.  From  this  period,  the  anatomy  of  the  nervous  system, 
whether  in  animals,  or  in  the  human  species,  has  been  contin- 
ually enriched  by  new  facts. 

§  737.  The  most  simple  animals  have  no  distinct  nervous 
system  (28.) 

The  first  in  which  it  begins  to  make  its  appearance  are  the 
radiated  animals,  and  in  particular  the  asteriaB  or  sea-stars,  in 
which  it  consists  of  soft  threads  and  small  enlargements  dis- 
posed around  the  mouth,  both  white  and  destitute  of  cincritious 
matter. 

In  all  the  other  invertebrate  animals,  the  nervous  system 
consists  of  two  more  or  less  approximated  cords,  brought  to- 
gether into  a  greater  or  less  number  of  knots  or  ganglia,  im- 
properly called  spinal  marrow  in  the  articulata,  always  united 
around  the  oesophagus  or  above  the  mouth  by  a  nervous  ring 
at  least,  and  often  by  a  ganglion,  of  which  the  volume  is  pro- 
portionate to  the  greater  or  less  degree  of  complexity  of  the 
head,  and  which,  in  the  mollusca,  receives  the  name  of  brain. 

In  all  these  animals,  the  two  teguments  and  their  muscles, 
the  organs  of  the  vegetative  functions  and  those  of  the  animal 
functions,  receive  similar  nerves.  . 

However,  there  already  occurs  in  the  nervous  ganglion  of 
the  cephalopoda,  (50)  an  evident  indication  of  a  nervous  cen- 
tre peculiar  to  the  organs  of  sensation  and  motion. 

§  738.  In  the  vertebrate  animals,*  the  nervous  system  con- 

*  See  M.  Tiedemann's  excellent  work:  Anatomic  und  Bildungsgcschicli!< 
des  gehirnst  &c.  Niirnberg,  1816;  translated  into  French  by  M.  Jourdan: 
Anatomic  du  cerveau,  contenant  thistoire  de  son  dcvdoppemcnt  dans  lefatus, 


OF  THE  NERVOUS  SYSTEM.  45.0 

sisls  of  a  central  mass  peculiar  to  that  class,  and  composed  of 
a  longitudinal  cord,  the  spinal  marrow,  in  which  the  ganglion' 
form  is  no  longer  apparent,  and  whose  upper  or  cranial  extre- 
mity, divided  into  the  pair  of  cords,  presents  enlargements 
and  developments,  which  together  form  the  encephalon.  These 
parts,  viewed  successively  from  behind  forwards,  are  the  ce- 
rebellum, the  tubercula  quadrigemina,  the  cerebrum,  properly 
so  called,  and  the  olfactory  lobes.  The  spinal  marrow  gives 
attachment  to  a  number  of  pairs  of  nerves  corresponding  to 
that  of  the  vertebra.  Each  of  these  nerves  is  furnished  with 
a  ganglion  near  its  central  extremity.  The  cranial  portion  of 
the  spinal  marrow  (the  medulla  oblongata)  furnishes  nerves  to 
the  organs  of  sense  and  the  other  organs  of  the  face,  and  to 
those  of  digestion  and  respiration.  Moreover,  there  exists  on 
each  side,  before  the  vertebral  column,  a  knotted  cord  (the 
great  sympathetic  nerve)  and  nervous  ganglia  and  cords  for 
the  heart  and  alimentary  canal,  a  particular  nervous  system, 
which  alone,  or  joined  to  the  pneumo-gastric  nerve,  resembles 
in  its  distribution  the  first  appearances  of  this  system  in  the 
animal  kingdom. 

§  739.  The  spinal  marrow,  which  is  hollow  in  the  ovipa- 
rous animals,  becomes  full  in  the  mammifera.  In  the  former 
it  occupies  the  whole  length  of  the  vertebral  canal;  in  the 
mammifera  it  extends  into  the  sacrum.  Its  volume  is  so  much 
the  greater  compared  with  that  of  the  brain,  or  the  latter  is  so 
much  the  smaller  compared  with  the  spinal  marrow,  as  we  ex- 
amine the  animal  series  farther  removed  frorTi  the  adult  man 
to  fishes.  It  is  cylindrical,  with  slight  bulgings  at  the  places 
where  the  nerves  of  the  limbs  are  attached  to  it.  Its  cranial 
portion  also  presents  enlargements  in  proportion  to  the  nerves 
there  inserted. 

The  cerebellum,  which  is  formed  by  the  posterior  or  resti- 
form  cords  of  the  spinal  marrow,  expanded,  reflected  and 
united  above  the  fourth  ventricle,  is  very  simple  in  the  osse- 
ous fishes,  in  many  of  the  cartilaginous  fishes,  and  in  the  great- 

avec  une  exposition  comparative  de  sa  structure  dans  les  animaux.  Paris, 
1823. — Desmoulins;  Exposition  succincte  du  dcvdoppcment  ct  dcs  functions 
du  systeme  cerebro-spinal. 


460  GENERAL  ANATOMY. 

er  number  of  reptiles.  In  the  others,  and  especially  in  birds, 
it  is  more  complex.  In  them  there  are  already  perceived  la- 
minae and  the  commencement  of  lateral  hemispheres;  but  in 
no  oviparous  animal  are  there  yet  seen  the  prolongations  des- 
tined to  form  the  annular  protuberance,  or  that  protuberance 
itself.  In  all  the  mammifera  we  find  the  lamellated  structure 
of  the  cerebellum,  lateral  hemispheres,  a  ciliary  body  in  the 
peduncles,  and  a  protuberance.  These  parts  are  the  more  de- 
veloped the  higher  we  rise  in  the  class  of  mammifera  towards 
man.  The  prolongations  of  the  cerebellum  at  the  tubercula 
quadrigemina  also  exist  in  all  the  mammifera.  The  ventricle 
of  the  cerebellum  is  common  to  the  four  classes  of  vertebrate 
animals. 

In  some  fishes  there  are  observed  encephalic  lobes  posterior 
to  the  cerebellum.  Such  are  those  which  correspond  to  the 
origin  of  the  nerves  of  the  electric  apparatus  of  the  torpedo. 

The  corpara  quadrigemina,  which  are  formed  by  the  de- 
velopment of  the  lateral  or  olivary  cords  of  the  spinal  marrow, 
appear  to  exist  in  all  the  vertebrate  animals,  although  there 
has  been  much  diversity  of  opinion  with  respect  to  their  de- 
termination. In  all  they  are  the  principal  point  of  origin  of 
the  optic  nerves.  In  all  they  form,  by  their  union  in  the  mid- 
dle line,  the  upper  wall  of  a  cavity  situated  between  the  ven- 
tricle of  the  cerebellum  and  the  third  ventricle.  They  are  so 
much  the  larger  in  proportion  to  the  encephalon  in  general, 
the  more  simple  it  is.  They  are  bigeminous  only  in  the  ovi- 
para,  and  are  quadrigeminous  only  in  the  mammifera.  The 
anterior  pair  is  larger  than  the  posterior  in  the  ruminantia,  so- 
lipeda  and  rodentia.  The  reverse  takes  place  in  the  carnivo- 
ra.  The  two  pairs  are  about  equal  in  the  quadrumana  and  in 
man. 

The  brain,  properly  so  called,  which  results  from  the  expan- 
sion of  the  anterior  or  pyramidal  cords  of  the  spinal  marrow, 
which  cross  each  other  in  all  the  mammifera  and  in  the  birds 
of  prey  only,  and  not  in  the  other  animals,  and  are  enlarged  by 
additional  fibres  from  the  optic  thalami  and  the  corpora  stria- 
ta,  presents  many  differences  in  its  volume  and  complication, 
which  are  in  general  proportionate  to  the  volume  of  these  thala- 


OF  THE  NERVOUS  SYSTEM.  461 

mi  and  these  corpora.  The  cartilaginous  fishes  have  no  brain. 
(Desmoulins.)  In  the  osseous  fishes  it  is  formed  by  the  optic  tha- 
lamus  alone,  which  is  solid.  (Desmoulins.)  In  reptiles  and  birds, 
it  is  formed  by  the  same  body,  which  is  hollow,  and  bears 
some  resemblance  to  the  hemispheres  of  the  mammifera;  but 
these  hemispheres  do  not  cover  the  tubercula  quadrigemina, 
and  have  as  yet  neither  lobes,  nor  circumvolutions,  nor  corpus 
callosum.  The  brain  of  the  mammifera,  which  is  formed  by 
a  recurved  medullary  membrane,  whose  fibres  come  from  the 
corpora  pyramidalia,  optic  thalami  and  corpora  striata,  gradu- 
ally approaches  to  that  of  man,  presenting  various  degrees 
of  organization.  The  rodentia  and  cheiroptera  occupy  the 
lowest  rank  in  this  respect.  Their  hemispheres  do  not  en- 
tirely cover  the  tubercula.  They  have  only  a  superficial  fis- 
sura  sylvii,  a  few  slight  grooves,  and  no  circumvolutions.  In 
the  carnivora,  the  ruminantia,  the  hog  and  the  horse,  the  he- 
mispheres, which  are  much  more  voluminous  and  prominent, 
cover  a  part  of  the  cerebellum.  Th'ey  have  circumvolutions 
and  anfractuosities,  but  are  still  destitute  of  posterior  lobes. 
In  the  quadrumana,  the  hemispheres  cover  the  cerebellum, 
but  the  posterior  lobe  is  still  destitute  of  circumvolutions. 

The  corpus  callosum,  which  is  formed  by  the  reflection  to- 
wards the  median  line  of  the  fibres  of  the  peduncles  spread 
out  in  the  hemispheres,  do  not  exist  in  the  ovipara.  In  the 
mammifera  its  extent  is  proportionate  to  that  of  the  hemi- 
spheres. It  is  accordingly  very  small  in  the  rodentia. 

The  lateral  ventricles,  which  are  formed  by  the  replication 
of  the  nervous  membrane  of  the  hemispheres,  are  propor- 
tionate to  the  extent  of  the  latter. 

The  fornix  does  not  exist  in  fishes.  We  find  the  first  traces 
of  its  pillars  in  reptiles,  and  still  more  distinctly  in  birds.  In 
all  the  mammifera  the  pillars  are  united  to  form  the  fornix. 
In  them  there  occur,  moreover,  the  septum  lucidum  and  its 
ventricle.  These  parts  are  proportionate  to  the  extent  of  the 
hemispheres. 

The  cornu  Ammonis  exists  only  in  the  brain  of  the  mam- 
mifera. The  unciform  eminence  exists  in  none  of  the  animals, 
excepting  perhaps  the  quadrumana. 


462  GENERAL  AXATOMY. 

The  pituitary  gland  exists  in  all  animals.  It  is  very  larirc 
compared  with  the  encephalon  in  all  the  inferior  classes.  The 
pineal  gland  appears  to  he  wanting  in  the  class  of  fishes. 

The  olfactory  lobes  terminate  the  encephalon  anteriorly. 
According  to  M.  Desmoulins  they  form  what  is  called  the 
brain  in  the  cartilaginous  fishes.  They  equal  the  brain  in  size 
in  many  osseous  fishes  and  reptiles.  They  are  very  small  in 
birds,  greatly  developed  and  hollow  in  many  mammifera,  and 
rudimentary  in  the  human  species. 

The  principal  differences  which  the  nervous  centre  presents 
in  man,  are,  therefore,  the  volume  of  the  cerebellum  and  ce- 
rebrum, compared  with  the  spinal  marrow,  the  tubercles  and 
the  olfactory  lobes;  the  size  of  the  lateral  lobes  of  the  cere- 
bellum compared  with  the  middle  lobe;  that  of  the  cerebial 
hemispheres,  and  their  posterior  prolongation;  the  existence 
of  its  posterior  lobe  and  its  appendages;  the  thickness  of  the 
nervous  membrane  which  forms  the  hemispheres,  the  size  of 
its  central  medullary  mass,  the  number  and  depth  of  its  sulci, 
the  number  and  thickness  of  its  convolution,  whence  results  a 
greater  extent  of  its  surface;  and,  lastly,  the  extent  of  the  cor- 
pus callosum. 

§  740.  The  ancients,  commencing  with  Galen,  and  many 
moderns,  have  regarded  the  nervous  system  as  having  a  single 
centre  in  the  encephalon,  and  prolongations  (the  spinal  mar- 
row and  nerves.)  It  has  already  been  seen  that  G.  Bartholin 
transferred  the  nervous  centre  to  the  spinal  marrow,  which  he 
did  from  the  consideration  that  fishes  have  a  very  large  spinal 
marrow,  and  a  very  small  encephalon,  and  yet  that  these  ani- 
mals possess  a  great  power  of  motion.  Bichat,  developing 
some  ideas  that  had  been  vaguely  advanced  before  him,  re- 
specting the  action  of  the  ganglia,  proposed  two  distinct  nerv- 
ous centres,  the  one  (the  cerebral,  or  encephalic  and  spinal) 
subservient  to  the  sensations  accompanied  with  consciousness, 
intellect,  and  voluntary  motion;  the  other  (the  ganglionary) 
subservient  to  the  functions  which  are  performed  without  con- 
sciousness and  volition.  In  this  latter  he  at  the  same  time 
placed  the  seat  of  the  passions.  M.  Cuvier  considers  the 
nervous  system  as  a  vast  net-work  embracing  the  whole  ani- 


OP  THE  NERVOUS  SYSTEM.  463 

mal,  and  furnished  with  numerous  centres  and  communicating 
cords.  Dr.  Gall  divides  the  nervous  system  of  animal  life  into 
those  of  the  spinal  marrow,  the  organs  of  sense,  and  those  of  the 
brain  and  cerebellum.  M.  de  Blainville  considers  the  nervous 
system  as  divided  into  as  many  parts  as  there  are  great  func- 
tions, and  defines  it  to  be  masses  or  ganglia  and  filaments,  some 
issuing  forth  and  going  into  the  organ  which  they  are  to  ani- 
mate, which  forms  the  particular  life;  others  entering,  and  all 
terminating  in  a  central  mass,  establishing  the  general  life,  and 
giving  rise  to  the  sympathies  and  relations.  The  central  part, 
according  to  this  ingenious  physiologist,  is  the  spinal  marrow; 
another  part  comprises  the  ganglia  of  the  organs  of  sense  and 
motion  ;  a  third  those  of  the  viscera,  viz.  the  cardiac  and  semi- 
lunar  or  coeliac  ganglions ;  the  fourth  and  last  comprehends  the 
great  sympathetic  nerve,  which  forms  a  centre  to  the  visceral 
ganglia,  and  which,  by  the  intervention  of  the  ganglia  of  sen- 
sation and  motion,  connects  them  with  the  central  mass. 

All  these  divisions,  which  may  be  justified  on  various  con- 
siderations, are  not,  however,  so  well  marked,  so  absolute  as 
their  authors  pretend.  In  man,  the  encephalon  or  some  one 
of  its  parts,  the  spinal  marrow,  where  it  is  embraced  by  the 
pons  varolii,  is  certainly  a  centre  to  which  the  functions  of  all 
the  other  parts  of  the  nervous  system  are  more  or  less  subser- 
vient. Indeed,  in  some  of  its  functions,  the  spinal  marrow 
may  be  considered  as  a  centre  nearly  independent;  it  is  the 
same  with  the  ganglions,  and  finally,  with  the  nerves;  for  no 
part  of  the  system  is  reduced  to  the  entirely  passive  condition 
of  a  conductor.  This  independence  of  the  nerves,  the  greater 
independence  of  the  ganglions,  and  the  still  greater  of  the 
spinal  marrow,  are  otherwise  so  much  the  more  distinctly 
marked,  as  this  or  that  function  is  concerned,  as  they  are  ob- 
served in  this  or  that  animal,  and  as  in  man  even  they  are  ob- 
served at  more  or  less  advanced  periods  of  development. 
These  propositions,  which  may  be  regarded  as  the  laws  of 
nervous  action,  will  be  developed  hereafter. 

It  is  sufficient  now  to  remark  that  there  is  no  absolute  sepa- 
ration  between  the  parts  of  the  nervous  system.     We  shall 
60 


464  GENERAL  ANATOMY. 

consider  it  successively  as  a  whole,  and  in  its  principal  parts, 
referring  the  details  to  special  neurology. 


SECTION  I. 

OF  THE  NERVOUS  SYSTEM  IN  GENERAL. 

§  741.  The  nervous  system*  forms  a  continuous  whole,  rami- 
fied and  reticulated,  all  the  parts  of  which  are  connected. 

§  742.  This  system  consists  in  a  central  mass,  in  nervous 
cords,  and  in  ganglions. 

The  central  nervous  mass,  which  has  not  received  a  particu- 
lar name,  and  which  is  designated  by  the  term  of  brain  in 
general,  and  sometimes  by  that  of  nervous  axis,  or  cerebro- 
spinal  organ,  consists  of  several  parts  which  are  distinguished 
by  their  situation,  into  spinal  marrow  or  rachiform  cord 
('PcytM^s  ^wTtos)  and  into  encephalon  (Efxt^axos);  by  their  form 
and  texture,  into  nervous  medulla,  and  into  cerebrum,  cere- 
bellum, and  tuberculaquadrigemina;  the  rudimentary  olfactory 
lobes  are  regarded  as  nerves. 

The  spinal  marrow  is  a  large  cord  single  and  median,  di- 
vided by  a  double  furrow,  into  two  lateral  portions,  and  by 
the  insertion  of  the  ligamenta  dentata^  into  anterior  and  poste- 
rior fascicles.  This  cord  contained  in  great  part  within  the 
vertebral  canal,  extends  into  the  cranium,  and  bears  there  the 

*  Th.  Willis,  Cerelri  anatomc  nervorumque  descriptio  et  usus,  Genevse, 
1676. — R.  Vieussens,  Neurographiauniversalis;  Lugd.  1684. — G.  Prochaska, 
de  structurd  nervorum  tract,  anat.;  Ejusd.  Comwentatio  de  function,  system, 
nerv.f  in  op.  minor. — Vicq-d'azyr,  liech.  sur  la  struct,  du  cerveau,  du  ccrvelet, 
de  la  moelle  allongee,  de  la  moelle  c'piniere,  et  sur  Furigine  dcs  nc?'fs,  &c.;  in 
Mem.  de  1'acad.  dessc.  de  Paris,  1781  and  1783. — A.  Munro,  Observ.  on  the 
nervous  system,'  Edinb.  1783. — Litdwig1,  /Scriptorcs  neurologici  minores  eelecti, 
&?e.y  Lipsiae,  1791-95,  4to. — F.  G.  Gall  and  Spurzheim,  liech.  sur  ksi/- 
nerv.  en  general,  etsur  cclui  de  cerveait  enpartioulicr,-  Paris,  1809. — Rolando, 
Saggio  sulla  vera  struttura  del  cevrello  ddl  'uomo  e  degli  animale,  e  sopra  le 
funzioni  del  sistema  nervoso,-  Sassari,  1809. — Cams,  Anat.  und  physiol,  dc? 
nervcn  systems;  Leipzig1,  1814. 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  465 

name  of  medulla  oblongata.  In  this  last  part,  besides  the  an- 
terior and  posterior  fascicles,  there  is  on  each  side  a  lateral 
fascicle. 

The  lateral  fascicles,  increased  by  the  corpora  olivaria,  are 
prolonged,  for  the  most  part,  into  the  tubercula  quadrigemina, 
and  terminate  there.  The  posterior  fascicles,  after  being  en- 
larged in  the  corpus  rhomboideus,  expand  in  the  cerebellum 
and  form  it;  extending  beyond,  they  unite  on  the  one  hand  at 
the  median  line,  under  the  medulla  oblongata,  where  they  form 
the  annular  protuberance  or  pons  varolii,  and  on  the  other  hand 
they  unite  with  the  tubercula  quadrigemina.  The  anterior  fasci- 
cles, after  mutually  crossing  each  other,  united  with  a  part  of 
the  lateral,  enlarged  in  the  optic  thalami,  and  the  corpora 
striata,  expand  in  a  radiated  manner  to  form  the  hemispheres 
of  the  brain,  and  unite  at  the  median  line  in  the  corpus  cal- 
losum. 

The  nervous  cords  or  the  nerves,  to  the  number  of  forty 
pairs  and  upwards,  join  the  medulla  by  one  extremity;  they 
present  a  certain  number  of  plexuses  where  they  communicate 
with  each  other;  numerous  ganglions  are  met  with  in  their 
course;  [tine  cords  terminate  by  another  extremity  in  the  two 
teguments,  the  organs  of  sense,  the  muscles,  and  in  the  coats 
of  the  vessels,  especially  of  the  arteries. 

§  743.  The  form  of  the  nervous  system  is,  in  general,  sym- 
metrical; the  symmetry  is  especially  marked  in  the  central 
parts,  still  more  so  in  the  spinal  marrow  than  in  the  encepha- 
lon,  where  the  surface  of  the  lobes  of  the  brain,  and  cerebellum 
always  presents  irregularities.  The  nerves  which  are  derived 
immediately  from  the  spinal  marrow,  are  all  symmetrical,  ex- 
cept the  pneumo-gastric,  which  is  distributed  to  asymmetrical 
organs:  all,  however,  in  their  ultimate  divisions,  cease  to  be  as 
rigorously  symmetrical  as  in  their  trunks.  The  ganglions  and 
the  nerves,  which  belong  to  the  asymmetrical  organs  of  vege- 
tative functions, participate  in  their  central  parts,but  especially 
in  their  divisions  and  peripherical  extremities,  in  the  irregu- 
larity of  these  organs. 

§  744.  The  situation  of  the  nervous  system  is  interior  and 
central  with  respeet  to  its  masses,  and  the  nervous  cords  also 


466  GENERAL  ANATOMY. 

are  deeply  seated:  the  extremities  alone  of  these  cords  reach 
to  the  two  teguments  of  the  surfaces  of  the  body. 

§  745.  The  nervous  system  is  formed  of  two  substances,  dis- 
tinguished by  their  colour  and  their  respective  situation,  into 
white  or  medullary,  and  gray  or  cortical. 

§  746.  The  white  nervous  substance,  called  also  medullary, 
medullaris,  because  that  for  the  most  part  it  is  enveloped  by 
the  other,  presents  several  shades  of  white. 

Its  consistence  varies  a  little  in  the  different  parts.  It  is  in 
general  less  elastic  than  gelatine,  but  a  little  more  glutinous, 
viscous  or  tenacious.  The  section  is  uniform  in  colour,  and  in 
appearance  homogeneous:  red  points  or  sanguineous  striae  are 
alone  perceptible  in  it.  This  substance  is  really  very  vascular; 
when  torn,  the  ruptured  blood  vessels  become  salient  on  its 
unequal  surface. 

The  white  nervous  substance,  plunged  for  some  minutes  in 
boiling  oil,  or  for  some  days  in  alcohol,  in  weak  nitric  or  mu- 
riatic acid,  in  acidulated  alcohol,  or  in  a  solution  of  corrosive 
sublimate,  augments  in  consistence;  and  if  it  is  then  attempted 
to  distend  or  to  tear  it  in  any  direction,  a  fibrous  appearance  is 
perceptible.     White  filaments  as  fine  as  hairs  can  be  separated 
from  it.     The  finest  fibrils  that  can  be  obtained  are  so  delicate 
and  so  closely  united  with  each  other,  that  it  is  very  difficult 
to  determine  any  thing  relative  to  their  length  and  the  diame- 
ter of  the  finest  of  them,  or  of  the  primitive  fibrils.     These 
fibrils,  parallel  or  concentric,  are  united  in  fascicles  which 
have,  with  respect  to  each  other,  different  directions.     It  is 
not  known  with  certainty  whether  this  fibrous  disposition  ex- 
ists throughout  the  nervous  system ;  it  has  been  found  wherever 
it  has  been  sought  for,  and  always  the  same  in  the  same  parts. 
This  fibrous  structure  is  visible  in  some  parts  of  the  nervous 
system,  without  any  preparation;  almost  every  where  more 
difficulty  is  experienced  in  tearing  this  substance  in  one  direc- 
tion than  in  another,  and  precisely  in  the  direction  which  the 
chemical  preparations  show  to  be  that  of  the  fibres. 

The  white  nervous  substance,  when  dried,  acquires  a  yel- 
lowish colour  and  a  corneous  appearance;  cut  into  thin  slices, 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  467 

it  becomes  semi-transparent,  plunged  into  water,  it  takes  again 
its  colour  and  its  opacity. 

§  747.  The  gray  substance,*  cinerea,  called  also  cortical, 
because  it  envelopes  the  preceding  in  many  places,  presents, 
like  it,  and  even  still  more  so,  varieties  in  shade:  it  varies 
from  lead  gray  to  a  blackish  brown  tint.  This  substance  is 
always  softer  than  the  white.  The  surface  of  its  section  is 
uniform,  and  presents  only  points  and  red  striae,  more  numer- 
ous still  than  in  the  medullary  substance.  This  substance,  in- 
deed, is,  in  some  points  at  least,  much  more  vascular  than  the 
white.  That  which  forms  the  cortical  substance  of  the  brain 
and  of  the  cerebellum  contains  so  many  vessels,  that  when  it 
has  been  well  injected,  and  afterwards  macerated,  it  appears 
under  the  microscope  entirely  vascular.  Albinus,t  however, 
affirms,  and  with  reason,  that  in  this  case  even  there  remains 
one  part  evidently  not  capable  of  being  injected,  or  extra-vas- 
cular. The  gray  substance,  submitted  to  the  same  chemical 
preparations  as  the  white,  does  not  present  an  entirely  similar 
fibrous  appearance  on  being  torn.  Submitted  to  the  action  of 
water,  the  gray  nervous  substance  becomes  softer,  swells  a  lit- 
tle, and  loses  a  great  part  of  its  colour.  Acids,  alcohol,  and 
especially  corrosive  sublimate,  whiten  it  at  the  same  time  that 
they  render  it  harder;  on  being  afterwards  dried,  it  becomes 
capable  of  being  pulverized.  The  colour,  a  little  variable  ac- 
cording to  the  races  and  individuals,  appears  to  be  a  product 
of  the  colouring  matter  of  the  blood. 

§  748.  The  two  nervous  substances  are  differently  intermin- 
gled with  each  other  in  the  different  parts  of  the  nervous  sys- 
tem: in  the  lobes  or  hemispheres  of  the  brain  and  cerebellum, 
the  gray  substance  forms  an  envelope  or  cortex  to  the  white; 
in  the  spinal  marrow,  the  gray  substance  forms  two  interior 
cords,  enveloped  by  the  white  substance;  in  the  medulla  ob- 
longata  and  in  the  crura  cerebriand  cerebelli,  masses  or  nuclei 
of  the  gray  substance  are  found  enveloped  by  the  white,  as 
well  as  alternate  layers  of  the  two  substances,  cords  or  fibres 
of  both,  which  cross  or  traverse  each  other  reciprocally;  iti 

*  Ludwig,  de  Cinerea  cerebri  substantia. 
f  dead,  annot.  lib.  I.  cap.  12. 


GENERAL  ANATOMY. 

the  ganglions,  a  peculiar  gray  substance,  traversed  by  white 
fibres;  finally,  in  the  nerves  white  fibres  alone. 

The  white  substance  alone  forms  a  continuous  whole.  The 
gray  substance,  on  the  contrary,  is  only  met  with  at  intervals; 
it  is  found  especially  where  the  central  extremities  of  the 
nerves  are  inserted;  it  has  been  supposed  even  to  exist  at 
their  peripheral  extremities,  and  especially  in  the  corpus  mu~ 
cosum  of  the  skin;  it  is  found  also  where  the  white  fibres  in- 
crease and  seem  to  expand,  as  in  the  crura  cerebri  and  cerebel- 
li;  finally,  it  is  found  at  the  surface  of  the  brain  and  cerebel- 
lum; it  has  been  thought  even,  but  without  proof,  that  it  ex- 
isted in  the  ganglions. 

The  fibrous  texture  of  the  nervous  substance  had  been  for- 
merly observed  in  the  white  substance  by  Malpighi,  but  he 
regarded  the  gray  substance  as  glandular. 

This  idea  of  Malpighi  respecting  the  gray  substance,  has 
been  for  a  long  time  admitted  in  conjunction  with  the  hypo- 
thetical opinion  that  the  nerves  are  hollow  or  canaliculated. 
Afterwards,  this  idea  of  Malpighi,  respecting  the  gray  sub- 
stance, gave  place  to  that  of  a  point  of  origin  (Gall,)  and  of  a 
centre  of  action,  (Ludwig,)  &c. 

§  749.  The  nervous  substance,  whether  white  or  gray,  on 
being  examined  with  the  microscope,*  and  enlarged  about 
three  hundred  diameters,  appears  in  all  its  parts  composed  of 
semi-diaphanous  globules,  united  by  a  transparent  arid  viscous 
substance.  These  globules  have  appeared  to  Delatorre  differ- 
ent in  size  in  the  brain,  cerebellum,  spinal  marrow,  and  nerves, 
the  largest  being  in  the  brain,  and  the  smallest  in  the  nerves; 
these  globules  have  appeared  to  him  heaped  together  without 
order  in  the  central  nervous  mass,  and  in  linear  series  in  the 
nerves;  as  to  the  liquid  in  which  they  are  contained,  it  appear- 
ed to  him  slightly  viscous  in  the  encephalon,  more  so  in  the 
spinal  marrow,  and  still  more  so  in  the  nerves.  These  glo- 
bules, and  the  liquid  which  surrounds  them,  furnished  and  re- 

*  J.  M.  Dellatorre,  Nuove  osserv.  micros.;  in  Napoli,  1776. — Prochaska  de 
struct,  nervor. — J.  and  Ch.  Wenzell,  dePenitiori  struct,  cerebri;  Tubing1. 
1812. — A.  Barba,  Osserv.  microsc.  sul  ccrvello  e  suite  parti  adjaccnti;  Napoli 
1807.— Home  and  Bauec,  Philos.  Trans.;  ann.  1821. 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.        469 

paired  continually  by  the  arrival  of  arterial  blood,  are  convey- 
ed, according  to  him,  from  the  brain,  as  from  a  centre,  to  all 
parts  of  the  body,  and  reciprocally;  their  flux  from  the  brain 
to  the  muscles  causes  motion,  their  reflux  from  the  senses  to 
the  brain  produces  sensation.  This  inadmissible  explanation 
should  be  separated  from  the  sufficiently  exact  anatomical  ob- 
servation upon  which  it  rests. 

Prochaska  having  examined  with  the  microscope  a  laminae 
of  nervous  substance  sufficiently  thin  to  be  transparent,  found 
that  it  resembled  a  sort  of  pulp  formed  of  innumerable  glo- 
bules or  round  particles;  by  the  action  of  water,  this  pulp  is 
divided  into  little  flocculi,  and  each  flocculus  is  composed  of  a 
certain  number  of  globules;  maceration,  prolonged  even  dur- 
ing three  months,  is  insufficient  to  separate  the  globules  from 
each  other.  He  concludes  that  the  uniting  medium  is  a  deli- 
cate cellular  tissue,  formed  in  part  by  sanguineous  vessels,  and 
in  part  by  prolongations  of  the  envelope  of  the  nervous  sys- 
tem: the  globules  appeared  to  him  different  in  size  in  the  same 
part  of  the  system;  he  estimates  the  size  of  those  of  the  brain 
and  cerebellum  at  about  one  eighth  part  of  that  of  the  globules 
of  the  blood;  as  to  the  structure  of  the  globules  themselves, 
the  most  powerful  microscopes  teach  us  nothing  on  that  sub- 
ject. 

Barba  has  observed  the  globules,  and  has  found  no  difference 
in  the  substance  which  unites  them,  in  the  different  parts  of 
the  nervous  system. 

The  brothers  Wenzell  have  added  some  observations  to 
these;  they  have  found  the  nervous  substance  throughout  form- 
ed of  globules  which  they  regard  as  vesicles  filled  with  medul- 
lary or  cineritious  substance,  according  to  the  parts;  the  glo- 
bules seem  to  touch  each  other  or  to  adhere,  and  nothing  is 
perceptible  between  them.  This  globular  appearance  resists 
desiccation,  the  action  of  alcohol,  either  pure  or  acidulated. 

Messrs.  Home  and  Bauer  have  published  two  different  re- 
sults of  microscopic  observations:  according  to  their  first  re- 
searches, the  fresh  brain  is  composed  of  fibres  formed  by  the 
reunion  of  globules  nearly  equal  in  size  to  those  of  pus.  Ac- 
cording to  their  new  observations,  the  nervous  substance  is 


470  GENERAL  ANATOMY. 

composed  of  white,  semi-transparent  globules;  some  of  thcrn 
equal  in  size  to  those  which  form  the  nucleus  of  the  coloured 
particles  of  the  blood,  others  smaller,  of  a  gelatinous  sub- 
stance, transparent  and  soluble  in  water,  and  of  a  liquid  simi- 
lar to  the  serum  of  the  blood:  the  proportion  of  these  three 
parts,  the  globules,  the  gelatine,  and  the  serum,  as  well  as  the 
size  of  the  globules,  gives  rise  to  the  principal  differences 
which  the  nervous  system  presents.  The  gray  substance  pre- 
sents few  distinct  fibres  not  globular,  it  is  formed  especially  of 
very  small  globules;  the  gelatinous  substance,  and  the  serous 
liquid  are'  very  abundant  in  it.  The  medullary  substance  of 
the  hemispheres  of  the  brain  and  cerebellum  contains  fibres 
formed  of  linear  series  of  globules  more  distinct  and  more 
abundant;  the  greater  part  of  the  component  globules  are  of  a 
greater  diameter:  the  gelatinous  substance  is  more  tenacious 
and  in  less  proportion  than  in  the  gray  substance.  The  cor- 
pus callosum  and  the  medulla  oblongata  have  especially  the  glo- 
bules of  mean  diameter,  the  gelatinous  substance  and  the 
serum  are  more  abundant  than  in  the  hemispheres,  and  the 
first  is  less  tenacious.  In  the  nerves,  globules  of  all  diameters 
are  found  united  into  fibres,  and  these  into  fascicles.  The  ge- 
latinous matter  in  question  is  found  again  in  the  blood,  where 
it  serves  as  a  uniting  medium  between  the  particles  of  the  co- 
louring matter  which  surrounds  the  globules. 

H.  M.  Edwards  is  publishing*  at  the  present  moment  mi- 
croscopic observations,  according  to  which  the  nervous  sub- 
stance of  the  encephalon,  of  the  spinal  marrow,  and  of  the 
nerves,  in  the  four  classes  of  vertebral  animals,  is  composed  of 
microscopic  globules,  1-300  of  a  millimetre  in  diameter, 
united  in  series  in  such  a  manner  as  to  form  primitive  fibres 
of  considerable  length. 

I  have  verified  these  observations,  the  importance  of  which 
is  so  much  the  greater,  as  similar  globules,  but  arranged  a 
little  differently,  are  found  in  all  the  tissues  of  animals. 

According  to  Carus,  the  nervous  globules  are  disposed  in 


la  structure,  clcmcntairc  dcs  principanx  tissus  organiquesdes 
animuux:   These  ;  Paris,  30  juillct  1823. 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  471 

clusters  in  the  central  masses  which  act  by  radiation,  and  in 
regular  lines  in  the  nerves  which  act  only  as  conductors. 

§  750.  The  cellular  tissue,  which  unites  the  nervous  fibrils, 
is  soft  and  little  apparent.  This  tissue  is  more  condensed  at 
the  surface;  where  united  with  the  vessels,  it  forms  a  mem- 
brane, more  or  less  dense,  more  or  less  vascular;  single  for 
the  nerves  (neurilema),  double  about  the  nervous  centre  (pia 
mater  and  dura  mater),  having  an  interval  with  contiguous 
walls  formed  by  a  serous  membrane  (tunica  arachnoides). 

§  751.  The  sanguineous  vessels  of  the  nervous  system  are 
very  numerous.  They  ramify  very  much  in  the  immediate 
envelope  of  this  tissue  (neurilema  and  pia  mater);  they  after- 
wards penetrate  into  the  gray  substance,  where  they  are  ex- 
tremely abundant;  they  penetrate  finally  into  the  white  sab- 
stance,  in  which  they  are  much  finer  and  less  numerous.  No 
lymphatic  vessels  have  been  discovered  in  the  nervous  sys- 
tem. 

§  752.  The  nervous  substance  has  been  examined  chemically 
by  Thouret,  Fourcroy,  and  Vauquelin. 

The  analysis  of  the  brain  by  Vauquelin,  has  given  the  fol- 
lowing results;  water  80.00;  white  fatty  matter  4.53;  red- 
dish fatty  matter  0.70;  albumen  7.00;  osmazome  1.12;  phos- 
phorus 1.50;  acids,  salts  and  sulphur  5.15. 

According  to  the  experiments  of  this  able  chemist,  the 
spinal  marrow  and  the  nerves  have  the  same  composition  as 
the  brain. 

John  has  recognised  that  the  gray  substance  contains  no 
phosphorus. 

Chevreul  has  found  in  the  blood  a  substance  characteristic  of 
the  nervous  matter,  cerebrine. 

§  753.  The  vital  properties  of  the  nervous  system  distin- 
guish it  essentially  from  all  other  organs;  besides  the  faculty, 
common  to  all  parts  of  living  bodies,  of  nutrition,  it  possesses 
another  active  property,  altogether  peculiar,  which  is  called 
nervous  force,  nervous  power,  nervous  influence;  manifests 
itself  by  the  functions  of  this  system  designated  collectively 
by  the  name  of  innervation. 
61 


472  GENERAL  ANATOMY. 

§  754.  Innervation*  too  much  restricted  by  those  who  confine 
it  to  sensation  and  volition,  holds  under  its  dependence,  in  a 
more  or  less  distinct  manner,  all  the  phenomena  of  life.  Modern 
physiologists  in  verifying  this  pre-eminence  of  the  nervous  sys- 
tem, have  been  enabled,  supporting  themselves  by  observations 
in  comparative  anatomy  and  physiology, by  observations  on  the 
development  of  the  embryo,  and  by  physiological  and  patho- 
logical observations  and  experiment,  to  establish  some  laws 
of  innervation.  In  general,  the  nervous  system  has  so  much 
the  more  influence  upon  the  rest  of  the  organization,  as  the 
animal  more  elevated  in  the  series  has  this  system  more  de- 
veloped. In  man  the  nervous  system  has  so  much  the  more 
influence  upon  the  functions,  as  the  individual  is  more  distant 
from  the  state  of  an  embryo,  and  at  the  same  time  has  this  sys- 
tem farther  advanced  towards  perfection.  The  influence  of 
nervous  action  upon  another  function  is  so  much  the  more 
clearly  marked,  as  this  function  is  further  removed  from  the 
state  of  a  vegetative  function.  The  influence  of  the  nervous 
centre  upon  the  rest  of  the  system  is  so  much  greater  and 
more  necessary,  as  the  centre  is  more  developed,  more  volu- 
minous relatively  to  the  remainder  of  the  system,  and  especially 
as  the  different  parts  of  the  central  mass  are  more  exactly  col- 
lected together  towards  a  single  point;  it  is  especially  in  this 
latter  respect  that  the  nervous  system  of  man  differs  from  that 
of  other  animals. 

§  755.  The  most  elevated  mental  operations  exercise  them- 
selves upon  results,  and  manifest  themselves  through  the  me- 
dium of  nervous  action;  it  is  then  true  to  say  that  man  is  an 
intelligence  served  by  organs. 

Actions  of  combination,  intermediate  between  sensation  and 
volition,  which  constitute  an  appearance  of  intelligence,  or  the 
advanced  instinct  of  vertebral  animals,  belong  also  to  nervous 
action. 

*  Rolando,  op.  cit.,  and  Journal  de  physiologic,  t.  iii. — George!,  de  la  Phy- 
siologic du  systeme  nerveux  etc.  Paris,  1821. — Flourens,  Recherches  physiques 
sur  les  proprietes  et  les  fonctions  du,  systeme  nerveux,  etc.;  in  Archives ge- 
ndrales  de  medicine,  vol.  ii. — Fodcrc,  Recher.  experiment,  sur  le  systeme 
gerveux;  in  Jour,  de  Physiol,,  torn.  iii. 


OP  THE  NERVOUS  SYSTEM  IN  GENERAL.  473 

The  most  limited  instinct,  which,  in  all  animals,  even  the 
most  imperfect,  necessarily  connect  certain  motions  with  cer- 
tain sensations,  is  also  a  nervous  action. 

Sensation  and  volition,  whatever  may  be  the  intermediate 
phenomena,  are  still  actions  of  the  same  kind. 

The  phenomena  of  irritation,  that  is  to  say,  impression  not 
perceived  and  involuntary  motion,  are  themselves  more  or 
less  dependent  on  nervous  action.  In  the  intestinal  canal,  in 
the  heart,  &c.,  usually  the  impression  is  not  perceived,  and 
the  muscular  contraction  is  not  voluntary,  but  notwithstand- 
ing the  nervous  system  intervenes;  for  if  in  the  regular  order 
the  impression  does  not  pass  beyond  the  ganglions,  and  if  the 
muscular  contraction  is  the  necessary  consequence,  which  is 
the  character  of  irritability,  in  certain  cases  of  extraordinary 
impressions,  sensation  results;  also  when  the  will  is  troubled 
by  the  passions,  the  interior  muscular  movements  are  per- 
ceived. In  the  vessels,  and  especially  in  the  arteries,  the 
nervous  action  is  very  evident.  In  the  cellular  tissue  the 
impression  and  the  contraction  closely  connected,  and  desig- 
nated by  the  single  name  of  tonicity,  appear  to  be  slightly 
dependent  on  the  nervous  system,  but  however  are  not  alto- 
gether foreign  to  it. 

The  nervous  influence  is  not  limited  to  the  organs  or  solid 
parts  alone,  the  blood*  experiences  its  effects. 

§  756.  The  nutritive  and  genital  functions,  also,  are  all  more 
or  less  dependent  on  nervous  action. 

Digestion,!  not  only  the  sensations  and  motions  which  take 
place  at  the  entrance  of  its  organs,  but  even  the  action  of  the 
stomach,  is  obedient  to  the  nervous  action;  it  has  been  known 
for  a  considerable  time  that  the  section  of  the  nerves  of  the 
stomach  deprives  this  organ  of  the  faculty  of  digesting  and 
pushing  forward  the  aliment  into  the  intestines. 
Respiration  is  not  less  dependent  on  nervous  influence;  the 

*  G.  A.  Treviranus,  Biokgia,  B.  4,  page  646. — Idem,  Fermischte  Schriften, 
&c.  B.  I.,  page  99. 

•j- A.  Brunn,  Experim.  circa  ligat.  nervorum. — Vavasseur,  de  1? influence  du 
systeme  nerveux  sur  la  digestion  stomacak:  These.  Paris,  12.  aout.  1823. 


474  GENERAL  ANATOMY. 

section  of  the  nerves  of  the  lungs  brings  on  speedily  asphyxia 
and  death. 

The  circulation,  especially  the  action  of  the  heart  and  capil- 
lary arteries,  is  equally  under  the  same  influence. 

Secretion  is  also  evidently  under  the  influence  of  the  nerves. 
Direct  experiments  show  that  the  section  of  the  nerves  of  an 
organ,  suspends  its  secretion.  Inhalation  or  absorption  is 
equally  modified  by  the  nervous  action.  Nutrition  or  organic 
formation,  without  being  an  immediate  result  of  the  nervous 
power,  notwithstanding  obeys  its  influence.  Animal  heat  is 
still  more  evidently  dependent.  The  physiological  experi- 
ments of  Messrs.  Brodie  and  Chossat  have  placed  this  influ- 
ence beyond  all  doubt:  the  chemical  and  physiological  experi- 
ments of  Messrs.  Dulong  and  Despretz  have  demonstrated 
that  this  heat  can  not  depend  entirely  on  respiration. 

We  see  even  in  generation,  that,  the  sensations  and  volun- 
tary motions  which  accompany  it,  the  motions  of  irritation, 
the  phenomena  of  secretion  of  the  sperm  and  formation  of  the 
ovules,  those  of  the  nutrition  and  growth  of  the  fecundated 
ovum,  are  all,  but  more  or  less  directly,  dependent  on  nervous 
action. 

§  757.  Sympathy  or  the  co-existence  of  two  phenomena  of 
formation,  of  irritation,  of  sensation  or  of  volition,  in  the  dif- 
ferent parts,  and  by  the  action  of  a  single  agent,  the  most  ex- 
traordinary fact  of  organization,  is  yet  an  effect  of  nervous 
action. 

§  758.  What  relation  is  there  between  the  different  parts  of 
the  nervous  system  with  respect  to  its  functions?  Is  there  a 
single  centre,  either  the  spinal  marrow,  or  the  encephalon? 
or  are  these  two  centres,  viz.  one  cerebral  and  one  ganglion- 
ary  ?  or  finally,  are  there  as  many  distinct  centres  as  there  are 
principal  organs  or  great  functions?  These  opinions,  all  found- 
ed upon  observation,  are  all  true  within  certain  limits. 

In  the  adult  man,  the  nervous  system  forms  a  single  system, 
all  the  parts  of  which  concur  in  the  action  of  the  whole,  in 
innervation,  but  besides  each  one  in  its  proper  function. 
Thus  the  brain  and  the  cerebellum,  besides  their  particular 
functions,  augment  the  energy  of  the  spinal  marrow;  this  last 


OP  THE  NERVOUS  SYSTEM  IN  GENERAL.  475 

augments  that  of  the  nerves.  In  the  adult  man,  the  encepha- 
lon,  and  more  precisely  the  mesocephalon,  that  is  to  say,  the 
cranial  extremity  of  the  spinal  marrow,  the  place  from  which 
spring  the  crura  cerebri  and  cerebelli,  is  truly  the  centre  of 
the  action  of  the  nervous  system. 

§  759.  What  relation  exists  between  the  two  substances  of 
the  nervous  system,  and  what  is  their  particular  use? 

Gall  regards  the  gray  substance  as  the  matrix  of  the  nerves, 
as  a  fertile  layer  in  which  the  nerves  take  root,  and  on  which 
depends  their  nutrition  and  growth.  If  Gall  means  by  this 
that  there  is  a  true  production  or  vegetation,  he  is  wrong:  for 
on  the  one  hand  no  part  is  the  product  of  another,  all  are  de- 
posited by  the  vessels,  each  one  in  its  place;  and  on  the  other 
hand,  the  white  substance  appears  before  the  gray,  both  in  the 
animal  kingdom  and  in  the  embryo.  If  he  wishes  to  speak 
only  of  an  insertion,  he  was  right.  We  ought  to  regard  with 
Ludwig,  Gall,  Carus,  and  Tiedemann,  the  gray  substance  as  a 
centre  of  activity,  as  fortifying  the  action  of  the  white  parts 
which  are  implanted  therein,  in  so  much  especially  as  it  pro- 
duces this  effect  by  the  great  quantity  of  arterial  blood  which 
traverses  it.  This  substance  abounds  in  the  spinal  narrow, 
where  the  largest  nerves  are  attached;  it  abounds  equally  in 
the  corpus  rhomboideum  of  the  cerebellum,  and  in  the  optic 
thalami  and  corpora  striata  of  the  brain,  as  well  as  at  the  sur- 
face of  these  two  organs  in  man. 

§  760.  What  is  the  particular  function  of  each  part  of  the 
nervous  system  ? 

The  nerves  (sect,  ii.)  conduct  the  impressions  of  the  sur- 
faces to  the  centre,  and  the  principle  of  motion  from  the  centre 
to  the  muscles  and  vessels. 

The  ganglions  (sect,  iii.),  in  consequence  of  the  quantity  of 
blood  which  is  distributed  to  them,  and  by  that  of  their  parti- 
cular texture,  modify  the  nervous  action. 

The  central  nervous  mass  fulfils  the  most  important  parts 
of  innervation;  it  is  the  instrument  of  intelligence. 

The  actions  of  combination,  intermediate  between  sensation 
and  volition,  are  also  functions  of  the  encephalon. 

Instinct  equally  intermediate  between  these  two  orders  of 


476  GENERAL  ANATOMY. 

phenomena,  if  it  is  attached  to  a  particular  nervous  part,  has 
probably  its  seat  in  the  superior  part  of  the  spinal  marrow. 

It  has  often  been  attempted  to  determine,  by  observation 
and  experiment,  the  organic  seat  of  sensation  and  volition. 

Rolando  regards  the  hemispheres  of  the  brain  as  the  seat  of 
these  two  actions,  and  the  cerebellum  as  the  organ  which  sends 
to  the  muscles  the  motive  principle  under  the  direction  of  the 
brain. 

According  to  Flourens,  the  spinal  marrow,  at  the  place 
where  it  is  surmounted  by  the  tubercula  quadrigemina,  is  the 
common  point  of  the  arrival  of  the  sensations,  and  of  the  de- 
parture of  the  nervous  influence  of  muscular  motion.  The 
cerebellum,  according  to  this  physiologist,  balances  the  mo- 
tions or  arranges  and  regulates  them;  according  to  him  the  ab- 
straction of  the  cerebellum  renders  the  animal  incapable  of 
acting  in  a  regular  and  proper  manner,  with  respect  to  station 
and  locomotion. 

Magendie,  supporting  his  position  by  the  experiments  of 
Lorry,  Legallois,  and  his  own,  thinks  that  sensibility  is  inhe- 
rent in  the  spinal  marrow.  This  able  physiologist  is  of  opinion 
that  the  will  or  the  faculty  of  determining  muscular  motions, 
resides  in  the  most  elevated  part  of  the  cranial  portion  of  the 
spinal  marrow,  even  in  the  optic  thalami  and  the  crura  cere- 
bri;  that  the  optic  thalami  are  necessary  to  lateral  motions; 
that  the  hemispheres  of  the  brain  are  necessary  for  the  pro- 
duction of  anterior  motions,  and  the  cerebellum  for  motions 
in  the  opposite  direction.  The  removal  of  one  or  the  other 
of  these  organs  suppresses  its  action,  and  determines  the  irre- 
sistible action  of  the  other;  the  removal  of  an  optic  thalamus 
determines  a  rotatory  motion. 

Foville  and  Pinel  Grandchamps  have  been  led  by  observa- 
tions in  morbid  anatomy,  to  which  they  have  joined  experi- 
ments on  animals,  to  establish  the  seat  of  sensibility  in  the 
cerebellum,  and  that  of  voluntary  motion  in  the  medullary 
substance  of  the  hemispheres;  the  anterior  part  and  the  cor- 
pora striata  for  the  abdominal  members,  the  optic  thalami  and 
the  posterior  part  of  the  hemispheres  for  their  superior  mem- 
bers. 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  477 

Difg6s,*  by  ingeniously  bringing  together  physiological  and 
pathological  facts,  places  the  seat  of  sensibility  in  the  cerebel- 
lum, and  that  of  voluntary  motion  in  the  hemispheres  of  the 
brain,  admitting  that  the  sensation  is  transmitted  to  the  side 
of  the  cerebellum  corresponding  with  the  impression;  on  the 
contrary,  as  has  been  known  for  a  long  time,  volition  is  trans- 
mitted from  one  side  of  the  brain  to  the  opposite  side  of  the 
body. 

These  different  opinions,  contradictory  in  some  points,  rest 
all  of  them  upon  facts  more  or  less  well  observed;  new  facts 
are  necessary  to  dissipate  the  uncertainties  which  still  remain 
upon  this  subject. 

The  transmission  of  sensation  takes  place  by  the  posterior 
part  of  the  spinal  marrow,  and  that  of  motion  by  its  anterior 
part.  There  are,  as  will  be  seen  hereafter,  special  nerves  for 
each  of  these  functions. 

The  spinal  marrow,  which  in  these  functions  has  only  the 
office  of  a  conductor,  is  the  seat  or  the  origin  of  the  principle 
of  irritability.  If  the  spinal  marrow  of  a  living  animal  be  di- 
vided in  its  middle,  the  posterior  part  of  the  body  becomes 
insensible  and  immoveable.  If  the  skin  of  this  part  of  the 
body  be  irritated,  the  irritation,  though  not  perceived,  deter- 
mines involuntary  motions  in  the  muscles  of  this  part.  If  the 
spinal  marrow  be  removed,  and  in  consequence  the  central 
connections  of  the  nerves  destroyed,  movements  of  irritation 
in  the  skin  can  be  no  longer  excited. 

The  circulation  is  under  the  influence  of  the  entire  spinal 
marrow,  and  of  all  the  motory  nerves  which  are  derived  from 
it;  the  particular  action  of  the  heart  also,  but  mediately,  being 
immediately  under  the  influence  of  the  sympathetic  nerve. 
Respiration  is  under  the  direction  of  the  superior  and  lateral 
part  of  the  spinal  marrow;  digestion  under  the  combined  in- 
fluence of  the  par  vagum  and  sympathetic. 

Secretion,  absorption,  vital  heat  and  nutrition,  are  under  the 
influence  of  all  parts  of  the  nervous  system. 

§761.  Nothing  is  known  respecting  the  manner  in  which 

*  Memoire  inedit. 


478  GENERAL  ANATOMY. 

the  nervous  system  acts.  This  fact  escaping  observation,  a 
multitude  of  hypotheses  have  been  proposed,  varying  with  the 
prevailing  doctrines  at  each  epoch. 

An  attempt  has  been  made  to  explain  nervous  action  by 
mechanical  hypotheses,  either  by  supposing  that  the  nervous 
fibres  could  vibrate  in  the  manner  of  cords,  or  by  admitting 
such  vibrations  only  in  their  elementary  fibrils,  or  in  the  spi- 
nal fibrils  which  have  been  supposed,  or  finally  by  an  oscilla- 
tion of  elastic  globules,  the  existence  of  which  has  been  ima- 
gined. 

Other  explanations  have  been  founded  on  the  supposition  of 
a  nervous  fluid,  either  material  and  visible,  or  more  generally 
an  incoercible  fluid;  and,  in  this  latter  supposition,  it  has  been 
called  sometimes  ether,  sometimes  phlogistic  or  magnetic,  lu- 
minous, electric,  latterly  galvanic,  according  to  the  objects 
which  have  engaged  at  different  epochs  the  attention  of  natural 
philosophers. 

Reil  has  proposed  on  this  subject  an  hypothesis  which  con- 
sists in  deriving  the  nervous  action  from  a  chemico-vital  pro- 
cess. He  attributes  in  general  the  action  of  organic  parts  to 
their  form  and  composition.  The  form  and  composition  of 
organic  parts  being  changed,  their  action  is  always  so;  and 
whenever  the  action  is  changed,  there  are  changes  observable 
in  the  parts;  so,  that  as  a  general  rule,  the  change  of  action  is 
a  consequence  of  the  change  of  composition  in  the  parts:  nerv- 
ous action  then  supposes  a  change  in  the  nervous  substance. 
What  appears  particularly  favourable  to  this  hypothesis  of 
Reil,  is  the  abundance  of  arterial  blood  which  is  distributed 
in  the  nervous  system,  and  especially  in  the  gray  substance, 
the  volume  of  which  is  always  proportionate  to  the  nervous 
activity  (759). 

§  762.  We  may,  independently  of  every  hypothesis,  consider 
the  nervous  action  as  a  general  fact,  and  observe  its  phenomena 
and  conditions.  The  phenomena  of  innervation  are  insensible 
in  the  nerve,  as  those  of  muscular  contraction  are  in  the  muscle: 
nothing  is  visible  there;  however,  some  facts  seem  to  indicate 
that  there  occurs  in  the  nervous  substance,  when  in  action,  a  mo- 
tion of  some  kind,  in  order  to  produce  sensation.  The  sensation 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  479 

resulting  from  the  impression  made  by  the  light  upon  the  eye 
is  not  instantaneous;  the  vibration  or  the  pressure  of  the  eye 
in  darkness  gives  the  sensation  of  light,  &c.  Many  other 
facts  collected  by  Darwin  seem  to  indicate  that  there  is  in  sen- 
sation a  molecular  movement  of  the  nervous  substance  which 
is  not  instantaneous.  On  the  other  hand,  many  facts  seem  to 
indicate  that  the  nervous  system  is  the  forming  and  conducting 
organ  of  an  imponderable  agent  analogous  to  electricity  or 
galvanism.  This  nervous  agent,  whose  existence  was  fore- 
seen by  Reil,  recognised  by  Humboldt  and  by  Aldini,  ad- 
mitted and  sustained  with  so  much  talent  by  Cuvier,  allows 
an  easy  explanation  of  all  the  phenomena  of  nervous  action, 
and  particularly  the  relation  which  exists  between  the  benumb- 
ing nervous  action  of  electrical  fishes  and  galvanic  phenomena 
on  the  one  hand,  and  ordinary  nervous  action  on  the  other; 
the  possibility  of  exciting  galvanic  phenomena  by  the  nerves 
and  muscles  alone;  the  possibility  of  exciting  muscular  con- 
tractions, the  chymifying  action  of  the  stomach,  the  respira- 
tory action  of  the  lungs,  &c.,  by  replacing  nervous  influence 
with  galvanic  action;  the  existence  of  a  nervous  atmosphere, 
acting  from  a  distance  on  the  nerves  and  muscles,  and  across 
the  solution  of  continuity  of  divided  nerves;  the  wrinkling 
which  takes  place  in  the  muscular  fibre  in  contraction,  and 
the  relation  of  the  ultimate  nervous  fibres,  transverse  with  re- 
spect to  these  wrinkles,  is  a  phenomenon  which  approaches 
certain  electro-magnetic  phenomena,  &c. 

These  opinions  have  appeared  so  probable  to  Rolando,  that 
he  has  sought  the  source  of  the  nervous  agent  of  contraction 
in  the  cerebellum,  which,  on  account  of  its  laminae,  has  ap- 
peared to  him  to  act  in  the  manner  of  a  voltaic  pile,  and  has 
admitted  in  sensation  a  molecular  motion  of  the  pulp. 

However  that  may  be,  the  nervous  power  is  weakened  and 
exhausted  by  intellectual  operations,  by  the  exercise  of  the 
senses,  of  the  muscles  and  of  the  encephalon,  and  still  more 
by  pain;  it  is  restored  by  rest,  food,  and  sleep.  Its  energy, 
generally  and  particularly,  is  relative  to  the  entire  mass  of  the 
nervous  system  and  of  its  parts,  and  especially  to  the  mass  of 
the  gray  substance,  which  is  the  most  vascular;  it  is  relative 
62 


480  GENERAL  ANATOMY. 

also  to  the  extent  of  surfaces.  It  remains  sometimes  after 
death,  in  the  nerves  and  muscles. 

This  power  seems  to  result  from  the  action  of  a  subtle  fluid, 
formed  by  the  organic  action  of  the  nervous  substance  bathed 
with  the  arterial  blood.  It  appears  that  this  fluid  is  formed 
throughout,  but  especially  where  there  are  masses  of  the  gray 
and  vascular  substance.  This  subtle  fluid  seems  to  traverse 
the  interior  and  the  surface  of  the  nerves,  form  an  atmosphere 
about  them,  and,  beyond  their  extremities,  penetrate  and  im- 
pregnate all  the  organs  and  the  humours  themselves.  The 
blood  in  particular  seems  to  be  penetrated  with  the  same  fluid, 
and  to  owe  to  it  the  essential  properties  which  distinguish  it 
during  Hfe. 

In  the  mean  time  arterial  blood  furnishes  the  nervous  sys- 
tem with  the  material  of  its  action;  the  arrival  of  arterial  blood 
is  also  a  condition  of  this  action. 

Asphleyxia,  the  cause  of  which  has  been  sought  for  in  the 
interruption  of  the  passage  of  the  blood  through  the  lungs, 
(Haller,)  in  the  arrival  of  the  blood,  which  had  remained  ven- 
ous, in  the  left  ventricle  (Godwin,)  in  this  blood  penetrating 
into  the  muscular  substance  of  the  heart  (Bichat,)  is  produced 
rather  by  the  dark  blood  penetrating  into  the  nervous  substance; 
syncope  in  the  same  manner  depends  on  the  innervation  be- 
ing cut  off  from  the  heart:  life  being  essentially  connected  with 
the  reciprocal  action  of  the  blood  upon  the  nervous  substance, 
and  of  the  nervous  substance  upon  the  blood. 

Does  the  nervous  agent  result  directly  and  solely  from  the 
reciprocal  action  of  the  blood  and  nervous  substance?  is  it 
drawn  from  without?  can  it  pass  from  one  individual  to  ano- 
ther? does  it  result  from  the  opposition  of  the  white  and 
gray  substances?  of  the  action  of  the  nervous  fibre  upon  the 
muscular  fibre?  Nervous  action  may  then  be  compared  to  a 
discharge  of  electricity. 

§  763.  Nervous  action  is  excited  or  put  in  play  by  external 
or  internal  stimuli. 

§  764.  The  first  moments  of  the  formation  and  develop- 
ment of  the  nervous  system,  can  not  be  observed.  Does  this 
system  exist  from  the  beginning,  and  does  generation  result 


OF  THE  NERVOUS  SYSTEM  IN  GENERAL.  481 

only  from  the  uniting  of  the  cellulo-vascular  system  furnished 
by  the  mother,  with  the  nervous  system  furnished  by  the  male 
(Rolando)?  Does  the  nervous  system  commence  with  the  for- 
mation of  the  cardiac  ganglion,  and  develope  itself  succes- 
sively by  the  great  sympathetic  nerve  and  the  rest  of  the  sys- 
tem* (Ackermann)? 

What  observation  teaches  us,  is,  that  the  nerves  and  the  spi- 
nal ganglions  are  formed  before  the  spinal  marrow,  and  this 
latter  before  the  encephalon,  that  is  to  say,  before  the  cere- 
bellum, the  tubercles,  and  the  brain. 

The  spinal  marrow,  at  first  open  behind  like  a  groove,  then 
canaliculate,  by  the  approaching  of  its  borders,  becomes  finally 
solid.  It  occupies  at  first  the  whole  length  of  the  vertebral 
canal.  The  white  substance  which  forms  the  exterior  is  first 
deposited;  the  gray  substance  being  deposited  afterwards  in 
the  interior,  fills  its  cavity. 

The  cerebellum,  tubercles,  and  brain,  which  constitute  at 
first  only  the  larger  parts  of  the  groove  of  the  spinal  marrow, 
reverse  themselves,  meet,  and  unite  at  the  median  line,  pre- 
senting in  the  different  places  of  their  development,  the  most 
exact  resemblance  with  the  same  parts  of  fishes,  reptiles,  birds, 
and  mammalia,  in  ascending  from  the  rodentia  to  the  quad- 
rumana  [739]. 

In  the  brain  as  in  the  rest  of  the  encephalon,  and  as  in  the 
spinal  marrow,  the  increase  in  thickness  takes  place  simulta- 
neously, exteriorly,  and  interiorly.  It  is  by  this  circumstance 
that  we  must  explain,  with  Desmoulins,  the  existence  of  a 
cavity  which  is  found  in  the  foetus,  within  the  centrum  ovale 
of  Vieussens,  between  the  interior  and  exterior  layers  of  the 
vault  of  the  lateral  ventricles. 

In  the  encephalon  as  in  the  spinal  marrow,  the  gray  sub- 
stance is  only  formed  after  the  white,  and  even  only  after  the 
fibres  of  this  latter  are  united  by  commissures  upon  the  me- 
dian line. 

After  birth,  the  increase  of  the  nervous  system,  previously  so 

*  Ackermann,  de  systematis  ncrvei  primordiis.  Heidelb.  1813. — Tiede- 
mann,  op.  dt. 


482  GENERAL  ANATOMY. 

rapid,  becomes  much  slower:  after  the  internal  ear  and  the 
eye,  it  is  the  part  of  the  body  which  then  grows  the  most 
slowly. 

In  old  age,  the  nervous  system  experiences  a  sensible  dimi- 
nution in  volume,  which  manifests  itself  in  the  encephalon  by 
the  narrowing  of  the  cranium,*  and  that  can  be  established 
also  by  measuring  the  spinal  marrow. 

§  765.  The  nervous  system  is  also  subject  to  many  errors 
of  conformation. t  One  case  is  known  of  a  total  deprivation 
of  the  nervous  system:  it  has  been  observed  in  an  acepha- 
lous foetus  reduced  to  a  little  trunk  without  form.  There  are 
several  cases  of  the  absence  of  the  encephalon  and  of  the  head. 
There  are  a  great  many  cases  of  the  total  absence  of  the  nerv- 
ous centre,  the  nerves  and  the  spinal  ganglions  existing. 
There  are  a  still  greater  number  of  casesof  theabsenceof  the  en- 
cephalon, the  spinal  marrow  existing,  as  well  as  all  the  nerves 
of  the  face  and  neck.  The  spinal  marrow  may  remain  open, 
hollow,  or  extended  throughout  the  whole  canal.  In  certain 
cases  the  cerebellum  and  tubercles  exist,  as  well  as  the  crura 
cerebri  and  their  optic  and  striated  enlargements,  and  the 
hemispheres  alone  are  wanting.  In  some  cases  the  hemispheres 
are  incomplete ;  the  middle  and  posterior  lobes  are  deprived 
of  furrows  and  convolutions.  Sometimes  the  corpus  callosum 
only  is  wanting ;  J  or  there  remains  a  cavity  within  the  hemi- 
sphere, or  in  the  septum,  &c.  The  cerebellum  may  present 
analogous  defects,  especially  in  the  number  of  its  laminae.  § 
All  these  cases  are  imperfections  or  defects  of  development. 

*  Tenon,  RecJierches  sur  le  Crane  humain,  Mem,  de  Plnst.  sc.  phys.  et 
Math.,  tome  I. 

f  A  Beclard,  Memoire  sur  les  foetus  actphales;  Paris,  1815. — Geoffrey 
Saint-Hilaire,  Phibs.  anatom.,  vol.  ii. — Breschet,  Diction,  de  Med.,  art. 
ActpTiale,  et  Jlnencephale. — C.  P.  Ollivier,  d* Angers,  Essaie  sur  Fanatomie  et 
le*  vices  de  conformation  de  la  moelle  tpiniere,-  Paris,  1823. — Id.  Traitt  de  la 
moelle  tpiniere  et  de  ses  maladies,  un.  vol.  8vo. — Laroche,  Essaie  d'anat. 
patfiol ,  sur  les  monstruosites  de  la  face,-  Paris,  1823. 

|Reil,  Jircliw.fur  die  physiologic,  torn.  xi. 

§  Malacarne,  Neuro  encephaktomia,-  Pavia,  1791. 


OP  THE  NERVOUS    SYSTEM  IN  GENERAL. 

There  may  exist  defects  of  symmetry,  and  defects  of  pro- 
portion between  the  different  parts  of  the  system. 

§  766.  The  consistence  of  the  nervous  system  is  sometimes 
changed.  Softening*  is  an  alteration  very  frequent  in  a  part 
of  the  central  nervous  mass.  The  softened  nervous  substance 
is  sometimes  so  much  so  as  to  be  almost  liquid.  Its  colour  is 
sometimes  milk  white;  at  other  times  it  is  yellowish,  rose 
coloured,  red,  or  brown.  This  alteration  is  met  with  in  the 
optic  layers,  in  the  corpora  striata,  in  the  hemispheres  of  the 
brain,  in  the  cerebellum,  in  the  medulla  oblongata,  and  even 
in  the  spinal  marrow.  It  gives  rise,  according  to  its  seat,  to 
different  derangements  of  the  sensations,  of  the  voluntary  mo- 
tions, and  of  the  other  functions  of  the  nervous  system.  It  is 
often  the  result  of  an  inflammation ;  in  some  cases  it  appears 
independently. 

The  hardeningt  of  the  nervous  system  has  been  observed  by 
Esquirol,  and  by  S.  Pinel,  who  has  very  well  described  it. 
The  hardened  nervous  tissue  presents  a  compact  mass,  organic 
in  appearance ;  it  resembles  in  colour,  consistence,  and  density, 
the  white  of  an  egg  much  hardened  by  cooking;  no  blood- 
vessels are  perceptible ;  it  appears  contracted.  The  hardening 
appears  to  affect  particularly  the  white  substance.  It  has  been 
observed  in  the  bodies  of  idiots,  in  the  brain,  cerebellum,  and 
spinal  marrow,  where  it  renders  the  fibrous  disposition  of  the 
white  nervous  substance  very  manifest. 

§  767.  The  nervous  system  is  subject  to  many  affections.  J 
the  principal  of  which  are,  in  the  central  mass,  sanguineous 
congestion  with  or  without  effusion ;  inflammation  and  its  va- 
rious degrees;  the  different  products  of  chronic  affections,  as 
encysted  abscesses,  the  production  of  tubercles,  of  schirrus, 
of  cancers,  of  fibrous  tumours  and  osseous,  of  hydatids,  and 
of  foreign  bodies.  The  membranes  which  envelop  the  cen- 
tral nervous  mass  are  equally  the  frequent  seat  of  sudden  con- 
gestions with  sanguineous  or  serous  extravasation,  of  acute  in- 

*  Rostan,  Recherches  sur  k  ramolUssement  du  cerveau,  2d.  edition;  Paris, 
1823. 

f  Pinel,  jr.  Recherches  sur  fendurcissementdu  syslemenerveux;  Paris,  1822. 
$  Lallemant,  Recherches  Jlnat.  path,  sur  Fenctphak  et  ses  dependences. 


484  GENERAL  ANATOMY. 

flammation  in  different  degrees,  of  chronic  inflammation;  acute 
and  chronic  hydrocephalus  are  also  met  with.  The  affections 
of  the  nervous  substance,  may  be  complicated  by  those  of  its 
membranes. 

The  affections  of  the  spinal  marrow  are  more  rare  in  man 
than  those  of  the  encephalon ;  the  contrary  takes  place  in 
animals. 

These  different  alterations,  according  as  they  are  acute  or 
chronic,  according  as  they  act  by  irritating,  by  destroying,  or 
by  compressing,  and  according  to  their  seat,  bring  on  different 
derangements  more  or  less  serious,  in  the  functions  of  the  nerv- 
ous system. 

§  768.  The  nervous  tissue  is  not  produced  accidentally ;  the 
affinity  established  between  this  tissue  and  the  encephaloid 
production,  by  Maunoir,  rests  upon  insufficient  analogies. 

The  nervous  tissue  on  being  wounded  cicatrizes,  when  the 
wound  is  of  such  a  nature  as  to  permit  the  individual  to  sur- 
vive. 

Wounds  of  the  encephalon,  and  of  the  spinal  marrow,  when 
they  are  not  mortal,  unite  like  those  of  other  parts.  Wounds 
of  the  encephalon,  with  loss  of  the  substance  of  its  envelopes, 
heal  by  the  formation  of  an  exterior  cicatrix.  This  fact  has 
been  observed  by  Dumeril,  in  salamanders,  and  by  many  sur- 
geons, in  the  human  species.  Wounds  with  loss  of  the  sub- 
stance of  the  brain,  the  cranium  remaining  entire,  heal  by  the 
formation  of  a  new  substance,  soft,  mucous  like,  which  does 
not  altogether  resemble  that  of  the  organ,  and  by  the  enlarge- 
ment of  the  corresponding  ventricle  of  the  brain.  Tearing  of 
the  encephalon,  produced  by  sanguineous  extravasation,  pre- 
sents, when  the  individual  survives,  remarkable  phenomena. 
The  blood  is  soon  surrounded  by  a  layer  of  organizable  lymph; 
this  layer  becomes  vascular  and  unites  with  the  nervous  sub- 
stance; the  blood  is  gradually  absorbed,  or  at  first  the  fibrine 
and  the  cruor,  and  then  there  remains  the  serum;*  or  at  first 
the  serum,  and  then  there  remains  a  fibrinous  coagulumt  to 

*  Riobe,  Observations  propres  a  rtsoudre  cette  question:  Vapopkxie,  &c., 
est-elle  susceptibk  de  gueriaon?  Paris,  1814. 
f  Rochoux,  Recherches  sur  Papopkxie;  Paris,  1814. 


ON  THE  NERVES  IN  GENERAL.  485 

which  the  cyst  unites:  in  the  end  the  whole  of  the  blood  being 
absorbed,  the  cyst,  contracting  by  degrees,  forms  adhesions, 
and  becomes  a  yellowish  cicatrix  which  perhaps  finally  dis- 
appears. 

The  cicatrices  and  the  other  alterations  of  the  nerves  will  be 
examined  hereafter. 

§  769.  The  nervous  system,  which  holds  so  high  a  station 
in  the  regular  exercise  of  the  functions,  fulfils  one  as  import- 
ant in  the  production  of  diseases:*  it  is  that  which  receives  and 
which  propagates  the  impression  of  morbific  causes,  which  de- 
termines the  irregular  motions  of  the  muscles,  of  the  heart, 
and  of  the  arteries,  which  produces  morbid  sympathies;  and 
as  its  action  extends  to  the  cellular  tissue  which  forms  the  base 
of  the  organs,  to  the  blood  which  penetrates  and  bathes  them, 
one  may  conceive  that  it  is  foreign  to  no  morbid  action,  and 
that  it  is  the  principal  agent  of  a  great  number  among  them. 

The  maladies  called  general,  essential,  or  dynamic,  have  no 
more  probable  seat  than  the  nervous  and  vascular  systems,  the 
centres  of  the  animal  and  vegetative  functions,  than  the  blood 
and  the  nervous  agent  which  traverse  them,  and  which  are  in 
a  mutual,  intimate,  and  necessary  dependance. 

It  is  in  the  regular  relation  of  these  two  great  systems  and 
of  their  functions,  that  life  and  health  consists;  it  is  from  the 
the  derangement  of  their  harmony,  that  disease  and  death  re- 
sult. 


SECTION  II. 

ON  THE  NERVES  IN  GENERAL. 

§  770.  The  nerves,t  nervi,  are  white  cords  formed  of  me- 
dullary filaments,  attached  by  one  extremity  to  the  nervous 

*  Georget,  op.  clt. — Lob  stein,  Discours  sur  la  preeminence  du  systeme 
nerveux;  Strasbourg",  1821. 

f  J.  C,  Reil,  ExercitatiowsanatomicxdestructuranervoTuni;  Halse,  1797, 
fol. 


486  GENERAL  ANATOMY. 

centre,  and  by  the  other  to  the  teguments,  the  organs  of  sense, 
the  muscles,  and  the  vessels. 

§  771.  The  anatomists  of  the  Italian  school  were  sufficient- 
ly well  acquainted  with  all  the  pairs  of  nerves  which  are  known 
at  the  present  time;  but  they  did  not  class,  number,  or  name 
them  as  is  now  done. 

Willis  gave  them  the  numerical  names  and  proper  names 
under  which  they  have  been  generally  known  since  his  time, 
viz. 

1st.  The  olfactory  nerves; 
2dly.  The  optic  or  visual  nerves; 
3dly.  The  motory  nerves  of  the  eyes; 
4thly.  The  pathetic  nerves  of  the  eyes; 
5thly.  The  fifth  pair; 
6thly.  The  sixth  pair; 

7thly.  The  seventh  pair,  composed  of  a  portio  dura  and 
aportio  mollis  or  auditory  nerve; 

Sthly.  The  eighth,  or  the  par  vagum,  with  its  spinal  or 
accessory  nerve; 

9thly.  The  ninth  pair,  or  the  motory  nerves  of  the  tongue; 
lOthly.  The  tenth  pair,  or  the  sub-occipital; 
The  nerves  of  the  spinal  marrow; 
And  the  intercostal  or  sympathetic  nerve. 
Soemmering  has  modified  the  division  of  Willis.     He  esta- 
blishes forty-three  pairs  of  nerves,  of  which  twelve  pairs  are 
nerves  of  the  brain:  dividing  the  seventh  pair  of  Willis  into 
seventh  or  facial,  and  into  eighth  or  auditory;  his  eighth  into 
ninth  or  glosso-pharyngeal,  into  tenth  or  par  vagum,  and  into 
eleventh  or  accessory,  the  twelfth  is  the  hypo-glossal;  and  re- 
jecting the  sub-occipital  among  the'spinal  nerves,  which  are 
then  thirty  pairs  in  number,  the  great  sympathetic  nerve 
forms  the  forty-third  pair.     These  modifications  have  been 
generally  adopted. 

Bichat  divided  the  encephalic  or  cranial  nerves,  into  those 
of  the  brain,  those  of  the  protuberance,  and  those  of  the  me- 
dulla oblongata.    This  division  is  not  founded  upon  exact  ob- 
servations. 
The  nerves  may  be  exactly  divided,  1st,  into  nerves  with 


ON  THE  NERVES  IN  GENERAL.  487 

double  roots,  one  arising  from  the  anterior  column  and  the 
other  from  the  posterior  column  of  the  spinal  marrow;  these 
are  the  spinal  nerves,  the  sub-occipital  and  the  trigemini,  or 
the  fifth  pair  of  the  cranial  nerves.  These  nerves  serve  at  the 
same  time  for  sensibility  and  for  muscular  motion.  2d,  Into 
nerves  with  a  single  root:  these  are  the  first,  second,  and 
eighth*  pairs,  or  the  olfactory,  optic,  and  auditory  nerves;  and 
the  third,  fourth,  and  sixth,  or  the  motor  nerves  of  the  eye; 
and  the  twelfth  or  the  motor  nerves  of  the  tongue.  These 
nerves  serve  exclusively,  some  for  sensibility,  the  others  for 
muscular  motion.  3d,  Into  respiratory  nerves,  vocal,  and  of 
expression:  they  arise  from  the  lateral  fascicle  of  the  superior 
part  of  the  spinal  marrow;  these  are,  according  to  Ch.  Bell,t 
to  whom  we  owe  an  exact  knowledge  of  them,  the  par  vagum, 
which  is  the  centre  of  this  system,  the  facial  nerve,  the  glosso- 
pharyngeal,  the  spinal  or  accessory,  the  diaphragmatic,  and 
the  external  thoracic.  4th,  Into  circulatory  nerves:  they  arise 
from  all  the  spinal  nerves;  these  are  the  great  sympathetic 
nerves.  These  last  and  the  par  vagum  are  connected  besides 
with  the  interior  tegument,  with  the  glands  and  the  interior 
muscles  in  general.  The  sympathetic  nerve  will  be  described 
separately  in  the  following  section. 

§  772.  The  form  of  the  nerves  is,  in  general,  cylindrical. 
Their  branches  are,  as  in  the  vessels,  larger  taken  together 
than  the  trunks  which  furnish  them:  the  nerves  consequently 
enlarge  from  their  origin  to  their  termination;  they  also  swell 
a  little  at  their  origin.  Their  surface  presents  wrinkles  or 
transverse  striae,  which  depend  on  the  elongation  which  they 
experience  in  different  movements;  these  wrinkles  are  easily 
perceived  with  a  lens,  especially  in  the  nerves  of  the  mem- 
bers. 

There  are  three  things  to  consider  in  the  nerves;  1st,  their 
origin;  2d,  their  course;  3d,  their  termination. 

§  773.  We  must  not  understand  by  origin  of  nerves,  the 

*  This  must  be  a  mistake  that  our  illustrious  author  has  overlooked  while 
correcting  the  proof;  for  the  auditory  nerve  is  the  seventh  and  not  the 
eighth  pair.  TBAKS. 

f  Phil  Trans.  1822,  part  1  and  2. 
63 


4SS  GENERAL  ANATOMY. 

point  from  which  they  spring  and  upon  which  they  vegetate, 
if  we  may  so  express  it:  this  origin  is  only  the  central  extre- 
mity of  the  nerve,  or  that  by  which  it  is  connected  with  the 
nervous  centre.  It  is  for  all  the  nerves  in  the  spinal  marrow 
and  in  the  medulla  oblongata;  no  one  arises  from  the  lobes  of 
the  brain  nor  from  the  cerebellum.  The  olfactory  nerve  is 
not  even  an  exception  to  this  rule;  this  nerve  arises  from  a 
prolongation  of  the  spinal  marrow,  which,  in  animals,  consti- 
tutes the  olfactory  bulb.  Sometimes  foetuses  are  found  de- 
prived of  the  brain,  and  in  which  notwithstanding  the  olfac- 
tory with  the  spinal  marrow  and  the  crura  cerebri  exist,  as  1 
have  had  occasion  to  observe  lately.  Bichat,  in  saying  that 
all  the  nerves  arise  from  the  medulla,  makes  an  exception  for 
the  optic  and  olfactory  which  does  not  really  exist. 

The  origin  of  the  nerves  is  often  more  deeply  situated  than 
it  appears  at  first;  so  that  the  point  from  which  they  detach 
themselves  is  often  not  their  true  origin:  the  fifth  pair, for  ex- 
ample, does  not  arise  from  the  pons  varolii,  from  which  it  ap- 
pears to  come,  for  the  pons  varolii  does  not  exist  among  ovi- 
parous animals,  where  the  origin  of  this  nerve  notwithstand- 
ing is  the  same  as  in  the  mammalia.  We  need  not,  however, 
seek  to  pursue  the  origin  of  the  nerves  beyond  the  reach  of 
the  senses,  and  suppose  them  to  set  out  from  the  brain  or  from 
the  cerebellum,  as  has  been  done  to  support  hypothetical  ex- 
planations. 

It  has  been  asked  if  the  nerves  cross  each  other  at  their  ori- 
gin; and  it  has  been  affirmed  without  hesitation  that  it  is  so, 
to  explain  pathological  phenomena  in  which  the  cause  and  the 
effect,  both  seated  in  the  nervous  system,  present  a  sort  of 
crossing.  Let  us  see  what  observation  teaches  on  this  subject. 
There  is  no  sensible  crossing  in  the  nerves  of  the  medulla  ob- 
longata. It  is  the  same  with  those  which  arise  from  it  where 
it  is  prolonged  into  the  cranium,  except  perhaps  the  optic 
nerves,  in  which  there  appears  to  exist  at  least  a  partial  cross- 
ing. Authors,  in  effect,  do  not  agree  as  to  the  mode  of  union 
of  these  nerves.  Their  crossing,  admitted  by  some,  denied  by 
others,  is  evident  in  fishes;  but  in  man,  although  in  most  cases 
the  atrophy  of  one  of  these  nerves  continues  on  the  opposite 
side,  observers  worthy  of  credit  assure  us  that  they  have  seen 


ON  THE  NERVES  IN  GENERAL.  489 

it  continue  on  the  same  side.  Dissection,  moreover,  does  not 
show  that  the  crossing  takes  place  in  all  the  fibres;  so  that  the 
opinion  of  those  who  think  it  only  partial  is  the  most  proba- 
ble. But,  this  exception  aside,  the  crossing  of  the  nerves  is 
far  from  being  demonstrated.  As  much  may  be  said  of  that  of 
the  two  sides  of  the  brain  and  cerebellum,  which  has  been  ad- 
mitted. The  anterior  pyramids  alone  present  this  disposition, 
which  explains  how,  in  affections  of  the  brain,  the  symptoms 
manifest  themselves  on  the  opposite  side  of  the  spinal  mar- 
row: thus,  when  this  last  is  divided  beneath  the  place  where 
the  crossing  of  the  pyramids  takes  place,  the  symptoms  appear 
on  the  same  side. 

Another  question  which  has  been  agitated  among  anatomists, 
is  to  know  if  the  nerves  unite  on  the  median  line  by  commis- 
sures analogous  to  those  which  are  found  between  the  corres- 
ponding sides  of  the  brain  and  cerebellum.  This  reunion  is 
evident  only  in  the  pathetic  nerves.  The  auditory  nerves  are 
also  sometimes  united,  at  their  origin,  by  white  striae,  which 
spread  over  the  bottom  of  the  fourth  ventricle;  but  these  striae 
are  far  from  being  constant,  and  are  generally  wanting  in  youth. 

Almost  all  the  nerves  have  a  deep  origin  from  the  gray  sub- 
stance, and  not  from  the  white,  which  covers  this  last,  and 
under  which  they  only  dip.  In  the  spinal  marrow  the  nerves, 
on  being  torn  up,  leave  a  pit,  which  shows  that  they  do  not 
stop  at  the  surface;  and  when  the  spinal  marrow  is  hardened, 
the  roots  of  the  nerves  may  be  followed  and  seen  traversing 
the  longitudinal  fibres  of  this  organ,  to  implant  themselves  in 
the  gray  substance.  In  the  cranium  this  disposition  is  also 
evident  as  respects  most  of  the  nerves.  The  auditory  alone 
have  their  origin  at  the  surface  of  the  medulla  oblongata;  but 
there  exists  at  the  same  time  the  gray  substance  in  the  place 
from  which  they  spring:  only  this  substance  is  superficially 
placed;  it  forms  the  gray  band. 

The  nerves  of  the  spinal  marrow  arise  with  two  roots,  one 
anterior  and  one  posterior,  as  has  been  said  already.  The  re- 
spective size  of  these  two  roots,  upon  which  there  have  been 
many  different  statements,  and  which  Gall  has  said  to  be  in 
favour  of  the  posterior  root,  is  so  really  only  in  the  bracJiial 
nerves;  the  contrary  takes  place  in  the  crural.  These  roots 


490  GENEKAL  ANATOMY. 

unite  in  theintervertebral  foramen,  where  the  posterior  presents 
a  swelling  or  ganglion,  with  which  the  anterior  is  simply  in 
close  contact.  This  last  does  not  concur  in  forming  this  gan- 
glion, as  is  said  in  the  greater  part  of  the  treatises  on  anatomy, 
although  this  peculiarity  was  pointed  out  long  ago  by  Haase, 
Munro,  and  Scarpa,  to  whom  even  the  discovery  has  been  at- 
tributed. Gall  only  remarks,  that  at  the  neck  the  anterior 
roots  of  the  spinal  nerves  are  soft,  pulpy,  and  reddish;  which 
has  deceived  the  anatomists  who  have  examined  this  region. 
In  the  cranium  the  nerves  present  no  such  distinct  roots.  At 
the  place  where  the  nerves  detach  themselves  from  the  me- 
dulla oblongata,  the  neurilema  abandons  them  or  becomes  soft- 
ened, and  confounded  with  the  pia  mater,  and  the  medullary 
substance  alone  is  continuous  with  that  of  the  encephalon. 
The  interior  filaments  of  the  nerve  are  sooner  abandoned  by 
the  neurilema  than  the  exterior  filaments:  it  follows,  that  where 
the  nerve  is  torn,  it  breaks  farther  outwards  than  inwards,  and 
there  remains  a  prominence  which  has  been  erroneously  com- 
pared to  an  apophysis  upon  which  the  nerve  is  implanted. 

§  774.  In  their  course,  the  nerves  branch,  preserving  near- 
ly the  same  size  in  the  interval  of  their  divisions.  These  last 
consist  only  in  a  separation  of  the  component  filaments,  and 
do  not  resemble  those  of  vessels.  The  divisions  of  the  nerves 
are  in  general  accompanied  by  those  of  the  vessels,  although 
they  do  not  always  exactly  correspond.  The  nerves  commu- 
nicate with  each  other  in  three  different  manners:  1st,  by  anas- 
tomoses; 2d,  by  plexus;  3*d,  by  ganglions. 

§  775.  By  anastomosis  is  understood  the  uniting  of  two 
nerves.  This  union  was  thus  named  by  the  ancients,  because 
they  regarded  the  nerves  as  vessels  in  which  the  nervous  fluid 
circulated,  and  compared  them,  in  this  respect,  to  arteries. 
This  expression,  which  has  been  criticized,  is  convenient 
enough;  for  there  is  not,  in  anastomoses,  a  simple  application 
of  the  nervous  filaments,  but  a  true  communication  of  these 
filaments,  a  junction  of  their  canal,  which  in  truth  contains  a 
substance  which  remains  there,  and  not  a  circulating  fluid,  as 
was  supposed  formerly.  The  anastomoses  take  place  some- 
times between  the  branches  of  the  same  nerve,  sometimes  be- 


ON  THE  NERVES  IN  GENERAL.  491 

tween  different  nerves,  rarely  between  the  nerves  of  one  side 
and  those  of  the  opposite. 

It  is  especially  in  the  nervous  arches  that  the  junction  of  the 
filaments  is  the  most  evident:  the  most  remarkable  of  these 
arches  is  that  which  results  from  the  union  of  the  par  vagum/of 
the  right  side  and  of  the  solar  plexus,  and  which  Wrisberg  has 
described  under  the  name  of  ansa  communicans  memora- 
biles. 

A  plexus  is  only  multiplied  anastomoses.  Scarpa*  has  giv- 
en a  very  good  description  of  them;  but  he  is  wrong  in  assi- 
milating them  to  the  ganglions.  The  manner  in  which  the 
four  last  cervical  pairs  unite  with  each  other,  and  with  the 
first  dorsal,  to  form  the  brachial  plexus,  furnishes  a  remarka- 
ble example.  The  cervical,  lumbar,  sciatic,  plexuses,  &c.  are 
also  examples  in  point.  These  plexuses  are  so  disposed  that  the 
nerves  which  arise  from  them  derive  ttyeir  origin  at  once,  for 
the  greater  part  at  least,  from  a  certain  number  of  the  nerves 
which  constitute  them. 

Bichat  admits  that  there  is  in  plexuses  something  besides  a 
simple  intimate  mixture  of  the  nerves.  Munro  says  that  they 
contain  gray  substance,  and  may  be  considered  a  new  origin 
of  the  nerves  which  depart  from  them;  but  this  is  by  no  means 
demonstrated. 

The  ganglions  consist  of  tumours  which  contain,  besides 
the  nervous  filaments,  a  substance  which  is  foreign  to  them; 
the  nervous  filaments  which  are  there  mingled  are  much  finer; 
they  present,  consequently,  a  greater  complication  than  the 
two  other  modes  of  communication.  They  will  be  examined 
after  the  nerves,  from  which  they  differ  in  several  characters. 

§  776.  The  termination  of  the  nerves  takes  place  after  they 
have  traversed  the  anastomoses,  the  plexuses,  or  the  gangli- 
ons, or  directly  without  their  being  interrupted  from  their  ori- 
gin. The  manner  of  their  termination  is  rather  obscure. 
They  are  seen  only  to  be  deprived  of  their  neurilema  towards 
their  latter  extremity,  and  to  become  in  consequence  very  soft; 
so  that  it  is  then  very  difficult  to  trace  them.  They  swell  in 

*  Anat.  annot.  de  gangliis  etplexubus. 


492  GENERAL  ANATOMY. 

general  as  they  approach  their  termination;  they  become  flat, 
and  are  then  no  longer  visible  while  it  appears  that  they  should 
still  be  so.  There  exists  two  hypotheses  upon  the  final  ter- 
mination of  the  nerves:  one  is  not  perhaps  better  founded 
than  the  other.  According  to  one  of  these  hypotheses,  the 
nerves  lose  themselves,  so  to  speak,  in  the  organs,  identifying 
themselves  with  their  substance,  which  is  imbibed  with  them, 
if  we  may  use  the  expression.  According  to  the  other,  which 
belongs  to  Reil,  the  nerve,  not  being  capable  of  expanding 
throughout  every  organ  at  once,  is  surrounded  with  a  nervous 
atmosphere  in  which  it  extends  its  action,  nearly  as  is  seen  in 
electric  phenomena.  What  has  led  to  these  hypotheses,  is 
this  remark,  that  the  nerves  expand  into  parts  the  extent  of 
which  is  much  greater  than  their  own,  even  after  they  are  di- 
vided as  far  as  the  eye,  armed  with  a  microscope,  can  follow 
them,  as  is  seen  in  the  muscles,  the  skin,, the  senses,  and  that 
notwithstanding  each  point  of  these  parts,  however  small  it 
may  be,  presents,  when  it  is  punctured,  the  same  phenomena 
as  when  the  nerve  itself  is  punctured. 

The  different  parts  do  not  receive  an  equal  number  of  nerves. 
The  organs  of  sense  are  those  which  contain  the  most:  the  eye 
and  the  ear,  present  membranous  expansions  entirely  formed 
of  nervous  substance.  The  skin,  particularly  at  the  hands 
and  the  lips;  the  mucous  membranes,  as  well  on  the  exterior 
as  the  interior;  the  glans  and  the  different  parts  of  the  vulva, 
placed  at  the  point  of  junction  of  these  membranes  with  the 
skin,  receive  most  nerves  after  the  principal  organs  of  the 
senses.  Then  come  the  exterior  muscles,  afterwards  the  in- 
terior, the  blood  vessels,  among  which  the  arteries  receive 
more  than  the  veins,  or  the  lymphatic  vessels  in  which  their 
existence  is  not  certain.  The  existence  of  the  nerves  is  doubt- 
ful in  the  other  parts,  or  in  those  which  have  cellular  fibre 
for  their  basis,  if  the  vessels  are  excepted,  as  the  cellular  tis- 
sue, the  serous  and  synovial  membranes,  the  cartilages,  the 
bones,  &c. :  these  parts,  in  fact,  do  not  appear  to  receive  nerves. 
Finally  the  corneous  parts  and  the  epidermis  are  certainly 
deprived  of  them.  It  is  possible,  on  the  contrary,  that  they 
exist  in  the  preceding  tissues,  and  that  their  softness  or  their 


ON  THE  NERVES  IN  GENERAL. 

extreme  tenuity  conceals  them  from  the  eye:  what  may  in- 
duce us  to  admit  this,  is  the  sensibility  which  these  tissues 
present  in  diseases.  It  is  true  that  the  hypothesis  according 
to  which  the  nerves  act  by  means  of  an  imponderable  fluid, 
susceptible  of  extending  its  influence  beyond  their  apparent 
termination,  may  explain,  to  a  certain  point,  this  phenome- 
non. According  to  this  hypothesis,  nervous  action  Is  trans- 
mitted beyond  the  nerves,  and  across  the  organic  substance, 
as  nutrition  takes  place  beyond  the  termination  of  the  arteries, 
by  a  sort  of  imbibition. 

It  is  worthy  of  remark,  that  in  some  circumstances  where 
there  exist  paralysis  of  sensation,  and  not  of  motion,  the  in- 
flammations which  develope  themselves  are  not  accompanied 
with  pain 5  which  would  lead  to  the  opinion  that  these  same 
cords  are  the  seat  of  general  sensation  and  of  painful  sensa- 
tion, peculiar  to  inflammation,  and  that  it  is  not  solely  the 
nerves  of  the  blood  vessels  which  cause  this  last  to  be  expe- 
rienced. 

§  778.  The  parts  in  which  the  peripheric  extremities  of  the 
nerves  terminate  in  the  most  evident  manner,  are  then  the 
tegumentary  membranes  and  the  senses  which  form  a  part  of 
them,  the  muscles  and  the  arteries. 

The  senses*  are  organs  more  or  less  complicated,  by  means 
of  which  external  bodies  are  perceived;  they  have  a  structure 
calculated  to  receive  an  impression;  they  are  connected  with 
the  nervous  centre  by  nerves  very  much  developed:  these 
organs  are  those  of  tact  or  touch,  of  taste,  of  smelling,  of  hear- 
ing and  of  seeing. 

The  muscles  are  connected  with  the  nervous  centre  by  nu- 
merous and  greatly  ramified  nerves  (662).  The  arteries  re- 
ceive a  great  number  of  nerves;  but  they  are  not  all  distributed 
in  the  same  manner:  1st,  some  only  accompany  them  and  sur- 
round them  as  the  ivy  surrounds  trees,  without  penetrating 
into  their  tissue,  unless  perhaps  after  having  accompanied 
them  for  a  greater  or  less  distance:  such  are  those  which  ac- 
company the  vertebral  arteries,  the  internal  carotids  and  the 

*  See  Blainville,  JPrincipes  d'Jlnal.  comparer,  t.  i.  Paris,  1822. 


GENERAL  ANATOMY. 

facial;  2d,  the  others,  adhering  to  the  external  membrane  of 
the  artery,  penetrate  with  it  into  organs  which  are  soft  and 
pulpy:  after  becoming  much  ramified  they  disappear,  and 
seem  to  dissolve  in  the  external  membrane;  3d,  finally,  not- 
withstanding the  denial  of  Behrends,  nervous  ramifications 
are  seen  traversing  the  external  membrane  of  the  arteries,  and 
terminate  in  the  middle  membrane.  The  nerves  of  the  arte- 
ries belong  either  to  the  sympathetic  nerves,  or  to  the  spinal 
and  trigemini. 

§  779.  The  structure  of  the  nerves  has  been  examined  by 
different  anatomists.  Delia  Torre  found  there  fibres  and  the 
globules  common  to  all  the  nervous  system;  Prochaska  and 
Reil  have  made  better  known  their  interior  disposition.  Ac- 
cording to  their  researches,  the  nerves  are  composed  of  cords, 
and  these  of  very  fine  filaments,  whose  tenuity  is  equal  to 
the  filaments  of  silk,  and  which,  in  the  optic  nerve  alone  are 
equal  in  size  to  a  large  hair.  These  filaments,  which  are  of 
the  same  nature  as  the  medullary  fibres  or  filaments  of  the 
brain  and  spinal  marrow,  differ  only  in  being  more  distinct, 
more  clearly  separated  from  each  other;  and  in  being  sur- 
rounded by  an  envelope  or  proper  membrane:  this  envelope 
is  called  neurilema,  neurhymen,  which  signifies  membrane  of 
the  nerves;  Galen  made  use  of  this  expression,  of  which  Reil 
first  made  a  precise  application.  The  neurilema  forms  a  ge- 
neral envelope  to  the  nerves,  and  furnishes  partial  envelopes 
to  the  nervous  cords,  as  well  as  to  the  component  filaments: 
it  resists  strongly.  When  it  is  empty,  it  represents  an  assem- 
blage of  little  canals.  These  canals  uniting  together,  open, 
into  each  other  at  different  distances.  It  is  not  then  correct 
to  say  that  the  nerves  are  composed  of  filaments  separate 
throughout  their  whole  length;  the  communications  of  these 
filaments  with  each  other  make  them  no  longer  the  same: 
examined  on  the  superior  and  inferior  part  of  the  nerve,  the 
nervous  cords  are  not  simply  adherent,  but  they  send  to  each 
other  reciprocal  filaments.  The  same  disposition  exists  in 
the  plexuses,  where  there  is  an  intimate  communication  be- 
tween all  the  nerves,  by  means  of  the  cords  and  filaments 
they  send  to  each  other.  What  the  plexuses  present  on  a 


ON  THE  NERVES  IN  GENERAL.  495 

large  scale,  is  seen  on  a  small  in  each  nerve;  and  the  cords 
themselves  are  merely  plexuses  of  nervous  filaments.  Towards 
the  origin  or  the  central  extremity  of  the  nerves,  the  neurile- 
ma  is  continuous  with  the  pia-mater,  but  only  in  that  portion 
of  it  which  constitutes  the  general  envelope  of  the  nerve:  the 
interior  sheaths  of  the  nervous  filaments  become  softened  and 
lost  insensibly,  so  that  these  are  naked  in  the  centre  of  the 
nerve.     The  nerves"  equall}7  are  seen  to  become  deprived  of 
their  neurilema  at  their  termination,  wherever  they  can  be 
traced  far  enough.     The  neurilematic  canals  do  not  present  in 
the  interior  a  smooth  and  polished  surface  as  is  the  internal 
surface  of  vessels;  they  give  out  a  multitude  of  prolongations 
which  traverse  the  medulla  of  the  nerve  and  sustain  it:  this 
last  is  not  free  and  moveable  in  the  nerve  which  it  owes  part- 
ly to  its  consistence,  but  which  is  also  owing  in  part  to  this 
disposition.     There  exists  cellular  tissue  about  the  general 
sheath,  aad  between  the  partial  sheaths  of  the  nerve,  as  has 
been  observed  with  respect  to  the  muscular  fascicles  and  the 
fibres  of  which  they  are  composed.     In  neuralgia,  this  tissue 
Is  sometimes  the  seat  of  an  oedema  and  of  an  infiltration  which 
renders  it,  in  certain  cases,  compact  and  close;  at  other  times 
of  a  sanguineous  congestion  or  of  a  very  great  redness,  as 
Cotugno  and  others  have  observed,  which  leads  to  the  opinion 
that  these  painful  affections  depend  on  its  inflammation.     Fat 
may  also  accumulate  in  this  tissue.     The  medullary  fibres, 
contained  in  the  canals  of  the  neurilema,  are  of  the  same  na- 
ture with  those  of  the  brain  and  spinal  marrow. 

§  780.  The  blood"  vessels  of  the  nerves  penetrate  between 
the  cords  of  which  they  are  composed,  and  divide,  for  the 
most  part,  into  two  branches,  one  direct,  the  other  retrograde. 
Their  number  is  considerable:  all  the  neurilema  is  perceived  to 
be  covered  with  them  in .. successful  injections;  they  are  seen 
with  a  lens  to  spread  over  even  the  neurilema  of  the  nervous 
filaments.  This  last  is  formed  of  fibrous  cellular  tissue  and  of 
blood  vessels.  No  lymphatic  vessels  of  the  nerves  are  known. 

§  781.  The  structure  of  the  nerves  is  not  exactly  the  same 
in  all.  In  the  greater  part  of  the  researches  which  have  been 

made  on  this  subject,  the  optic  nerve  has  been  chosen,  because 
64 


496  GENERAL  ANATOMY. 

the  nervous  filaments  are  larger  in  it,  and  that  it  is  easy  to  fill 
the  neurilematic  canals.  But,  this  nerve  differs  from  the 
others  by  its  canals  being  separated  by  common  partitions 
which  are  detached  from  the  interior  of  the  general  sheath. 
The  structure  of  the  nerves  has  however  also  been  observed 
in  other  nerves:  it  is  especially  in  those  of  the  muscles  where 
the  filaments  are  more  distinct  than  in  the  nerves  of  the  senses 
or  of  the  skin,  that  these  observations  have  been  made. 

§  782.  Reil,  to  whom  we  owe  almost  all  that  is  known  about 
the  structure  of  the  nerves,  has  well  indicated  the  means  by 
the  aid  of  which  this  structure  may  be  observed.  By  washing 
the  nerve  with  water  and  nitric  acid,  at  the  end  of  a  certain 
time,  the  neurilema  is  entirely  destroyed,  and  there  remains 
medullary  filaments  which  may.  be  seen  crossing  each  other, 
resting  against  each  other,  nearly  like  the  optic  nerves  in  their 
commissure.  On  the  other  hand,  plunging  a  nerve  into  ley, 
which  may  be  regarded  as  an  alkaline  solution  of  subcarbonate 
of  soda,  the  medullary  substance  is  destroyed,  and  the  neuri- 
lematic sheaths  are  obtained.  To  hinder  them  from  becoming 
effaced,  they  may  be  filled  with  air:  which  is  very  easy,  by 
forcing  this  fluid  into  one  of  them,  since  they  all  communi- 
cate with  each  other;  the  nerve  is  then  tied  at  its  two  ends: 
when  dried  in  this  state,  it  presents,  on  being  cut,  a  multitude 
of  little  canals  opening  into  each  other,  which  gives  it  the 
aspect  of  the  interior  of  a  reed.  These  observations,  which 
have  been  repeated  many  times,  after  Reil,  demonstrate  the 
two  different  substances  of  which  the  nerve  is  composed. 

The  observations  of  Home,  upon  the  optic  nerve,  have 
shown  that  the  medullary  filaments  of  which  it  is  composed, 
augment  in  number,  and  diminish  in  volume,  from  the  origin 
to  the  termination. 

§  783.  The  nerves  have  little  or  no  elasticity;  they  have  no 
sensible  motion,  either  of  oscillation,  or  vibration,  when  irri- 
tated in  the  living  animal.  The  irritation  of  a  nerve  produces 
severe  pains,  and  brings  convulsive  contractions  in  the  muscles. 

§  784.  The  functions  of  the  nerves  are  to  conduct  sensation 
and  motion.  They  transmit,  with  incalculable  velocity,  voli- 
tion from  the  nervous  centre  to  the  muscles,  and  convey  to 


OF  THE  NERVES  IN  GENERAL.  497 

the  centre  the  sensations  produced  by  the  impression  of  ex- 
ternal agents.  Cutting  or  tying  them  interrupts  their  func- 
tions, and  renders  the  parts  below  insensible  and  immoveable. 
Irritation  above  the  interruption  produces  sensations  of  pain 
similar  to  what  the  irritation  of  the  extremity  of  the  nerve 
would  have  produced.  Irritation  below  the  interruption  pro- 
duces contractions,  like  those  which  result  from  the  irritation 
of  the  origin  of  the  nerve. 

785.  It  has  been  an  object  of  research,  since  Herophilus 
and  Galen,  whether  there  were  not  particular  nerves  for  sen- 
sation and  others  for  motion.  It  was  soon  perceived  that 
there  are  sensorial  nerves,  as  the  first  pair,  the  second,  and  the 
auditory;  motory  nerves,  as  the  third,  the  fourth,  the  sixth,  the 
hypoglossal,  &c. ;  and  mixed  nerves,  as  all  the  spinal  nerves 
which  distribute  themselves  to  the  skin  and  muscles  of  the 
trunk  and  members;  and  as  the  sub-occipital  and  trigemini. 
But  the  paralyses  and  anestheses,  which  have  been  observed 
sometimes  united,  and  sometimes  separate  in  the  parts  of  the 
body  to  which  the  nerves  with  double  roots  distribute  them- 
selves, led  to  the  supposition  that  these  nerves  were  composed 
of  distinct  sensorial  and  motory  filaments.  The  experiments 
of  Ch.  Bell,  those  of  Magendie,  and  my  own,  have  clearly  de- 
monstrated that  the  posterior  roots  of  the  spinal  nerves  are 
the  sensorial,  and  the  anterior  the  motory. 

§786.  The  nerves  are  not  entirely  confined  to  the  functions  of 
simple  conductors:  they  have  an  activity  of  their  own  which 
manifests  itself  when  they  are  separated  from  the  nervous  cen- 
tre; but  this  activity  is  much  augmented  by  that  of  the  spinal 
marrow,  as  that  of  the  spinal  marrow  is  by  the  influence  of  the 
encephalon;so  that  the  cutting  off  of  the  encephalon  diminishes 
much  the  activity  of  the  spinal  marrow,  and  that  of  the  spinal 
marrow  lessens  much  that  of  the  nerves,  and  the  nearer  to  a 
muscle  a  nerve  is  cut  off,  the  more  the  nervous  influence  upon 
its  contraction  is  diminished. 

§  787.  Have  the  nerves  a  power  of  formation  or  regenera- 
tion such,  that  on  being  cut  across,  their  reunion  shall  have 
the  nervous  texture  and  perform  its  functions?  such  even  that 
on  being  divided  with  loss  of  substance,  they  are  reproduced? 


GENERAL  ANATOMY. 

These  questions  have  much  occupied  physiologists,  and  espe- 
cially Fontana,  Monro,  Michaelis,  Arnemann,  Cruikshank, 
Haighton,  Meyer,  &c.  Most  of  these  experimenters  have  re- 
solved in  the  affirmative  the  questions  relative  to  nervous  re- 
production. Arnemann  alone,  supporting  himself  like  the 
others  upon  a  series  of  experiments,  has  adopted  a  contrary 
opinion. 

I  have  made,  with  one  of  my  pupils/  a  great  number  of  ex- 
periments in  order  to  resolve  these  questions.  There  results 
from  our  observations,  1st,  that  the  division  of  a  nerve,  pro- 
duced by  a  ligature,  is  constantly  followed  by  the  exact  reunion 
of  the  two  ends  of  the  nerve,  and  by  the  prompt  re-establish- 
ment of  its  functions; 

2d.  That  the  imperfect  section  or  the  puncture,  which  has 
been  accused  of  giving  rise,  in  man,  to  so  serious  accidents, 
does  not  produce  accidents  in  animals,  and  that  the  reunion, 
and  the  re-establishment  of  the  functions  take  place  very 
promptly; 

3d.  That  the  complete  section  of  a  nerve  in  a  part  little  sub- 
ject to  motion,  as  for  example,  along  one  of  the  two  bones  of 
the  fore-arm  of  a  dog,  in  the  neck  of  the  same  animal,  along 
one  of  the  bones  of  the  fore-arm  in  man,  &c,,is  ordinarily  fol- 
lowed promptly  enough  with  an  exact  reunion,  and  complete 
re-establishment  of  the  functions  ; 

4th.  That  in  parts  much  subject  to  motion,  as  in  the  vicinity 
of  an  articulation,  when  a  nerve  is  divided,  there  takes  place, 
besides  the  primitive  retraction  which  is  constant,  an  acci- 
dental retraction  and  variable  according  to  the  motions  of  the 
part.  In  this  case  the  reunion  is  long  in  forming;  it  is  imper- 
fect even  if  it  takes  place:  the  re-establishment  of  the  functions 
is  imperfect  also,  or  even  altogether  wanting.  It  is  to  this 
that  must  be  referred  the  results  of  some  of  the  experiments 
of  Meyer,  and  the  permanent  paralysis  which  is  said  to  result 
from  the  section  of  the  radial  nerve  at  the  inferior  part  of  the 
arm; 

5th.  Finally,  that  when  there  is  considerable  loss  of  sub- 

•iiilion 
Paris,  1822. 


OF  THE  NERVES  IN  GENERAL, 

stance  of  a  nerve,  either  by  excision,  or  in  a  contused  wound 
with  destruction,  there  remains  a  large  interval  between  the 
two  ends  of  a  nerve,  and  the  functions  are  never  re-established, 
whatever  may  be  the  affected  nerve ;  which  is  sufficient  to  prove 
that  the  anastomoses  are  of  no  avail,  when  the  re-establishment 
of  the  functions  takes  place. 

We  may  then  conclude  that  nerves  divided  reunite;  and 
that  when  the  reunion  does  not  take  place,  it  depends  only  on 
the  distant  separation  of  the  extremities,  brought  about  by  the 
motions  of  the  parts,  or  by  a  loss  of  substance. 

§  788.  When  a  nerve  has  been  divided,  there  takes  place 
during  the  first  days,  about  the  ends,  at  their  surface,  and  in 
their  interval,  an  exudation  of  organizable  matter;  the  sur- 
rounding cellular  tissue  is  penetrated  by  the  same  matter,  and 
has  lost  its  permeability.  In  this  state  the  ends  of  the  nerve 
are  simply  agglutinated  together,  and  to  the  surrounding  parts; 
the  functions  are  still  suspended  as  they  were  immediately 
after  the  division;  the  two  ends  of  the  nerve,  which  are  swol- 
len, especially  the  superior,  the  surrounding  cellular  tissue, 
and  the  organizable  matter,  take  more  consistence,  and  become 
very  vascular.  In  this  state,  which  continues  some  time,  the 
two  ends  of  the  nerve  are  united  by  an  organized  vascular  sub- 
stance; but  there  is  still  no  communication,  of  nervous  action 
between  the  two  ends.  After  a  time  the  surrounding  cellular 
tissue  ceases  to  be  compact  and  vascular;  the  intervening  sub- 
stance, more  or  less  long,  according  to  the  kind  of  wound  and 
the  concomitant  circumstances,  diminishes  by  degrees  in 
volume,  consistence,  and  redness;  takes  the  appearance  and 
texture  of  nerve  (a  texture  established  by  the  application  made 
by  Meyer  of  nitric  acid  to  the  nervous  cicatrix)  departing  from 
the  extremities  to  the  middle  of  their  interval,  and  finishes  by 
fulfilling  the  functions,  so  much  the  sooner,  and  so  much  the 
more  exactly,  as  there  was  no  interval  between  the  ends  of  the 
nerve,  as  in  the  case  of  ligature,  or  a  very  small  one,  as  in  the 
case  of  simple  section,  or  of  a  very  short  excision  in  a  part 
little  subject  to  motion.  On  the  contrary,  when  the  interval 
is  considerable,  the  reunion  does  not  take  place,  or  it  takes 
place  only  by  a  cellular  tissue  which  does  not  acquire,  at  a 


500  GENERAL  ANATOMY. 

certain  distance  from  the  extremity,  the  nervous  properties 
and  structure.  The  time  necessary  for  the  complete  re-es- 
tablishment of  thestructure  and  functions  is  not  exactly  known; 
it  has  been  certainly  exaggerated  by  those  who  have  advanced 
that  several  years  are  required:  it  may  be  estimated  at  about 
six  weeks  or  two  months. 

§  789.  The  section  of  the  pneumo-gastric  and  trisplanchnic 
nerves  united,  as  they  are  in  the  dog,  produces  constantly 
death,  when  it  is  done  on  both  sides  at  once.  It  is  upon  these 
nerves  that  the  re-establishment  of  the  functions  and  the  sepa- 
ration of  the  tissue  may  be  studied  simultaneously,  according 
to  the  experiments  of  Cruikshank,  Haighton,  and  our  own. 

The  following  is  what  we  have  seen  take  place  in  this  sec- 
tion, repeated  at  different  intervals. 

Having  cut,  on  the  same  day,  the  two  pneumo-gastric  nrvese 
in  two  different  dogs,  one  died  thirty  hours  after  the  operation, 
the  other  more  than  sixty-six  hours  after  this  double  section. 
Another  animal,  after  an  interval  of  nine  days  between  the 
two  sections,  died  in  the  night  of  the  fourth  and  fifth  day.  In 
a  fourth,  the  second  section  having  been  made  at  the  end  of 
twenty-one  days,  death  took  place  only  on  the  twenty  fifth  day, 
after  this  second  section.  Finally,  upon  another  animal,  the 
second  section  was  made  thirty-two  days  after  the  first,  and 
the  animal  survived  an  entire  month.  At  this  period,  that  is 
to  say,  two  months  after  the  first  section,  we  found  the  nerve 
which  was  first  divided,  completely  reunited.  This  dog  fell 
under  an  empyema  which  developed  itself  in  the  left  cavity 
of  the  chest.  Finally,  Haighton  cut  the  second  pneumo-gastric 
nerve  six  weeks  after  the  first,  and  the  animal  survived  nine- 
teen months,  after  which  time  it  was  killed.  It  has  been  pre- 
tended that  the  nervous  action,  in  the  same  manner  as  galvan- 
ic action,  might  re-establish  itself  across  a  substance  differ- 
ent from  the  nervous  tissue,  as  a  fluid  or  moist  cellular  tis- 
sue; it  has  been  pretended,  als6,  that  the  nervous  action  might 
take  place  at  a  distance,  and  pass  over  the  interval  which 
exists  between  the  ends  of  the  nerve;  it  has  been  pretended, 
finally,  that  the  re-establishment  of  the  functions  might  take 
place  by  anastomosing  branches.  If  it  was  by  the  one  or  the 


OP  THE  NERVES  IN  GENERAL.  501 

other  of  these  two  first  causes  that  the  nervous  action  had  been 
continued,  this  action  would  not  have  been  suspended  a  single 
instant,  and  the  animals  would  not  have  died  in  either  of  the 
experiments  above  cited.  As  to  the  re-establishment  of  the 
nervous  functions  by  anastomoses,  it  is  contradicted  by  a  great 
number  of  cases,  in  which  the  nerve  having  been  cut  in  certain 
subjects,  and  in  others  excised  or  destroyed  by  cautery,  the 
functions  have  been  re-established  in  the  first  instance,  and  not 
in  the  second.  The  re-establishment  by  anastomoses  is  com- 
pletely proved  false  by  an  experiment,  which  consists  in  again 
cutting  on  the  same  day,  in  the  place  of  reunion,  the  pneumo- 
gastric  nerves  cicatrized  after  previous  section  of  these  two 
nerves  at  proper  times.  The  animal,  which  has  survived  un- 
til this  moment,  dies  in  the  space  of  one  or  two  days. 

It  is  then,  neither  by  the  interposition  of  a  substance  simply 
moist  between  the  two  ends  of  a  divided  nerve,  nor  by  the 
action  from  a  distance  of  the  nervous  system,  nor  finally  by 
anastomoses,  that  the  re-establishment  of  the  nervous  func- 
tions takes  place,  but  by  a  true  nervous  cicatrix.  We  see  in 
effect  the  functions,  at  first  altogether  destroyed,  become  gra- 
dually re-established,  and  follow,  in  their  re-establishment,  all 
the  process  of  organic  union.  It  can  not  be  denied,  however, 
that  the  nervous  action  is  propagated  to  a  certain  degree,  from 
one  part  to  the  other  of  a  divided  nerve:  this  is  proved  by  the 
experiments  of  Wilson  Philip,  which  have  been  repeated  in 
France.* 

§  790.  The  nerves  are  subject  to  other  alterations  besides 
those  which  result  from  physical  injuries;  such  are  inflamma- 
tion or  neuritis,  tumours  or  neuroma.  Some  consist  in  a  sub- 
cutaneous tubercle  graniformor  pisiform,  hard  and  very  pain- 
ful; others  in  a  schirrous  tissue  more  or  less  voluminous. 
Neuralgia  and  local  insensibilities,  paralysis  and  partial  con- 
vulsions, are  the  ordinary  results  of  local  affections  of  the 
nerves;  besides,  these  local  affections  extend  sometimes  to  the 
nervous  centre,  and  give  rise  to  general  neuroses; 

*  Vavasseur  dt  f  influence  du  systeme  nervettx  sur  la  digestion  stomacak; 
Paris,  1823. 


GENERAL  ANATOMY. 

SECTION  III. 

ON   THE    GANGLIONS   AND    SYMPATHETIC    NERVE. 

§  791.  The.  nervous  ganglions  are  round  or  obround  bodies, 
formed  of  medullary  nervous  filaments  and  of  a  peculiar  sub- 
stance, placed  upon  the  course  of  the  nerv.es,  and  especially 
the  nerves  of  vegetative  functions. 

§792.  The  name  of  ganglions,  yayysuoy,  was  employed  by 
Hippocrates,  to  designate  tumours  of  the  sheaths  of  the  ten- 
dons. Galen  first  applied  it  to  the  nodosities  of  the  nerves, 
from  comparison  with  morbid  ganglions.  J.  Riolen,  jr.  and 
Vieussens  have  made  use  of  the  same  name;  others  have  em- 
ployed that  of  gangliform  plexus:  that  of  ganglion  is  gene- 
rally used  now. 

Gall,  Reil,  Walter,  Blainville,  &c.,  have  extended  the  mean- 
ing of  the  word  ganglion,  and  have  applied  it  to  the  gray  sub- 
stance which  exists  in  the  interior  of  the  spinal  marrow,  to  the 
masses  of  gray  substance  which  are  found  in  the  medulla  ob- 
longata  and  in  the  crura  cerebri  and  cerebelli,  as  the  corpora 
olivaria,  the  corpus  rhomboideum  of  the  cerebellum,  the  optic 
thalami  and  the  corpora  striata;  it  has  been  exte.nded  even  to 
the  olfactory  lobes,  to  the  hemispheres  of  the  brain,  to  the  tu- 
bercula  and  to  the  cerebellum;  finally,  the  ganglions  have  been 
confounded  with  the' plexus  and  with  sensorial  nervous  expan- 
sions. These  are  forced  relations,  which  have  already  been 
controverted  by  Walther  the  elder,  Reimer,  and  Soemmering. 
It  is  not  in  this  sense  that  the  word  ganglion  is  employed  here. 

§  793.  The  ganglions  have  been  described  and  studied  par- 
ticularly by  Meckel,*  Jonstone,t  Haase,J  Scarpa,§  Bichat,|| 
Weber, IF  and  especially  Watzer. **  The  opinion  of  anato- 

*  Histoire  de  1'acad.  de  Berlin,  ann.  1749  &  1753. 

f  Essays  on  the  use  of  the  gang-lions,  etc.  1771. — Medical  essays,  etc. 
1795. 

%  De  gangliis  nervnrum,-   Lipsias,  1762. 
'  §  De  nervnrum  Gangliis  et  plexubus,-  Afutfme,  1779. 

Jl  Aruitornit  Generate. 

^  De  systemate  nerveo  organ.,-  Lipslsp^  1817. 

**  De  corporis  humani  Gangliorumfabricd  atqueusu;  Bt.rolini,  1817. 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVES.  503 

mists  and  physiologists  on  the  texture  and  function  of  gan- 
glions, may  be  referred  to  two  principal  ones  differently 
modified:  some,  regarding  them  simply  as  condensed  plexuses, 
consider  the  nerves  which  depart  from  them,  only  as  distant 
divisions  of  the  spinal  and  cranial  nerves;  others,  considering 
the  ganglions  as  special  nervous  centres,  consider  the  nerves 
which  emanate  from  them  as  independent  of  the  cerebral  sys- 
tem. We  shall  see  that  these  two  opposite  systems  ought 
to  be  combined  and  mutually  modified. 

§  794.  The  inferior  animals,  that  is  to  say,  the  radiata,  the 
mollusca,  and  the  articulata,  have  nervous  enlargements  which 
have  been  assimilated  to  the  ganglions  of  the  vertebrata.  But 
in  the  invertebral  animals  the  same  nerves  belong  to  all  kinds 
of  organs  and  functions,  whilst  in  the  vertebrata  the  great 
sympathetic  nerves  (and  to  a  certain  degree,  the  pneumo-gas- 
tric  nerves),  belong  especially  to  the  organs  of  vegetative  func- 
tions. Weber  has  compared  the  spinal  ganglions  of  the  ver- 
tebrata to  the  ganglions  of  the  inferior  animals. 

In  vertebral  animals,  which  alone  have  true  nervous  gan- 
glions comparable  to  those  of  man,  we  see  these  ganglions 
augment,  especially  those  of  the  sympathetic  nerve,  and  the 
pneumo-gastric  nerve  diminish  astheencephalon  becomes  de- 
veloped, so  that  fishes  have  the  smallest  sympathetic  nerve, 
and  the  largest  pneumo-gastric,  and  vice  versa  in  the  mammalia, 
as  if  the  vegetative  functions  ought  to  be  farther  removed 
from  the  influence  of  the  encephalon,  in  proportion  as  this 
organ  is  lesstsubject  to  instinct. 

§  795.  The  ganglions  have  been  divided  into  several  kinds 
by  those  who  have  described  them  with  the  greatest  accuracy. 
Scarpa  divides  them  into  simple  or  spinal,  and  into  compound. 
Weber  divides  them  into  auxiliary  ganglions  (de  renforce- 
ment,)  which  are  those  of  the  spinal  nerves,  and  some  of  those 
of  the  cranial  nerves;  and  into  ganglions  of  origin:  these  are 
those  of  the  sympathetic  nerve,  to  which  he  joins  the  orbitary 
and  the  maxillary.  Ribes*  divides  the  ganglions  into  three 

•* Expose  sommairede  quelques  recherches  anat.  phys.  et  pathol.,  in  the  Mem. 
de  la  soc.  med.  cumulation,  vol.  viii. 
65 


504  GENERAL  ANATOMY. 

series:  he  ranges  in  the  first  the  rachidian  or  spinal;  in  the 
second  those  which  are  found  in  the  course  of  the  trisplanch- 
nic;  and  all  that  are  situated  more  internally  in  the  third. 
Wutzer  divides  them  into  ganglions  of  the  cerebral  system,  of 
the  spinal  system,  and  of  the  vegetative  or  sympathetic  sys- 
tem. I  divide  them  into  two  kinds:  list,  the  ganglions  of  the 
encephalo-spinal  nerves,  some,  the  most  numerous  and  the 
most  regular,  belonging  to  the  nerves  with  double  roots, 
others  placed  in  the  course  of  the  nerves  with  a  single  root; 
2d,  the  ganglions  of  the  two  sympathetic  nerves,  some  form- 
ing a  double  longitudinal  series,  and  others  near  the  median 
line. 

§  796.  The  number  of  ganglions  is  very  great,  as  will  be 
seen.  They  are  all  situated  in  the  trunk;  Lancisi  was  wrong 
in  stating  that  they  existed  in  the  members.  Their  size  varies 
from  that  of  an  olive  to  that  of  a  grain  of  millet;  their  form 
is  round,  ova!5  lenticular,  &c. 

§  797.  The  ganglions  are  composed  of  two  internal  sub- 
stances: the  first  medullary  and  white;  the  second  pulpy  and 
of  a  reddish  gray.  The  medullary  substance  is  collected  into 
cords  and  filaments,  like  the  sensorial  and  motory  nerves. 
These  interior  medullary  filaments  are  visibly  the  continua- 
tion of  the  nerves,  connected  with  the  ganglions.  The  coeli- 
ac  ganglion  is  the  only  one  where  this  continuation  is  not 
clearly  manifest.  These  filaments  are  recognized  by  their  co- 
lour and  form.  The  action  of  alkalies  and  acids,  upon  them, 
renders  them  manifest,  even  in  the  midst  of  the  ganglions,  as 
nervous  medullary  filaments. 

These  filaments,  on  penetrating  the  ganglions,  become  de- 
prived of  their  neurilema,  which  unites  intimately  with  the 
exterior  membrane  of  the  ganglion.  These  filaments  have 
their  surface  less  exactly  defined  than  in  the  nerves;  their  sur- 
face appears  more  loose,  as  if  blended  or  intimately  united 
with  the  adjacent  substance.  These  medullary  filaments  have 
otherwise  considerable  tenacity. 

§  79S.  The  second  substance  of  the  ganglions  establishes 
not  only  the  difference  between  the  nerves  and  ganglions,  but 
between  the  ganglions  and  the  plexuses.  This  substance  has 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVES.         505 

been  much  neglected  by  anatomists,  who,  considering  the  gan- 
glions as  plexuses  more  condensed,  have  regarded  it  only  as 
destined  to  separate  or  to  unite  the  nervous  filaments  (Scarpa), 
or  to  perform  the  functions  of  the  cellular  tissue  (Haase). 
The  matter  which  surrounds  the  medullary  filaments  of  the 
ganglions  is  a  particular  cellular  tissue,  the  interstices  of  which 
are  filled  with  a  mucilaginous  or  gelatinous  pulp,  of  a  reddish 
ash  colour,  yellowish  in  some  ganglions.  This  colour,  like 
that  of  other  organs,  does  not  depend  solely  on  the  quantity 
of  blood  which  they  receive. 

This  secondary  substance  is  not  equally  abundant,  and  is  not 
altogether  united  to  the  medullary  substance  in  the  same  man- 
ner in  all  the  ganglions. 

§799.  Scarpa  says  that  this  pulpy  matter  is  fatty  in  very  fat 
subjects.  Meckel  appears  to  be  of  the  same  opinion.  Bichat 
thinks,  on  the  contrary,  that  the  ganglions  are  never  trans- 
formed into  fat.  The  observations  of  Wutzer,  and  my  own, 
are  entirely  in  union  with  those  of  Bichat.  In  very  fat  sub- 
jects, there  accumulates,  under  the  'membrane  of  the  gangli- 
ons, fat,  which,  when  in  great  quantity,  surrounds  not  only 
the  ganglion,  but  compresses  it  and  diminishes  its  size;  not- 
withstanding it  is  itself  never  changed  into  fat. 

§  800.  The  ganglions  are  enveloped  by  a  cellular  or  fibrous 
membrane,  which  differs  in  the  different  kinds  of  ganglions. 

§  801.  The  blood-vessels  of  the  ganglions  are  very  numer- 
ous. The  arteries  come  from  the  neighbouring  trunks;  they 
ramify  first  in  the  membrane,  where  they  form  a  net-work; 
delicate  branches  penetrate  into  the  filamentous  and  pulpy 
tissue  of  the  ganglion;  sometimes  arterial  branches  penetrate 
into  the  ganglion  with  the  nervous  filaments,  and  accompany 
them.  The  veins  offer  a  similar  distribution.  Nothing  is 
known  concerning  the  tymphatic  vessels  of  these  organs. 

§  802.  The  medullary  filaments  present  no  interruption  in 
the  ganglions;  they  establish  a  continuity  or  an  uninterrupted 
connexion  between  the  nervous  cords,  in  the  course  of  which 
the  ganglions  are  placed.  These  medullary  filaments  form 
connexions  in  the  interior  of  the  ganglion,  and  traverse  them 
in  different  directions,  in  such  a  manner  as  to  unite  together  all 


506  GENERAL  ANATOMY. 

the  cords  which  belong  to  them.  From  this  results  the  irre- 
gular figure  and  the  interior  complication  of  the  lateral  and 
median  sympathetic  ganglions,  which  are  placed  in  the  middle 
of  many  nervous  cords,  and  the  regular  ovoid  form,  as  well 
as  the  simply  longitudinal  direction  of  the  filaments  of  the 
spinal  ganglions. 

§  803.  Bichat  tried  some  chemical  experiments  on  the  gan- 
glions, which  proved  that  there  was  nothing  common  between 
their  substance  and  that  of  the  brain.  Some  anatomists,  how- 
ever, having  continued  to  confound  with  the  ganglions  the 
enlargements  of  the  central  nervous  mass,  composed  of  white 
substance  and  of  gray,  Wutzer  commenced  a  series  of  compa- 
rative chemical  experiments  upon  the  ganglions,  and  upon  the 
intermixture  of  the  white  and  gray  substances  of  the  brain 
and  cerebellum.  It  follows  from  these  experiments,  that  there 
is  a  real  difference  between  these  two  objects;  that  the  gan- 
glions differ  from  the  nerves  by  a  greater  proportion  of  gela- 
tine, and  still  more  from  the  encephalon  by  the  excess  of  ge- 
latine, by  a  greater  quantity  of  albumen,  and  by  a  less  pro- 
portion of  fat.  Lassaigne*  has  made  a  chemical  analysis  of 
the  guttural  ganglions  of  the  horse,  and  has  found  them  com- 
posed, 1st,  of  fibrine,  for  the  greater  part;  2d,  of  concrete  al- 
bumen in  small  quantity;  3d,  of  soluble  albumen;  4th,  of  tra- 
ces of  fatty  matter;  5th,  of  phosphate  and  carbonate  of  lime. 
Lobstein  has  observed  that  although  they  resist  putrefaction 
longer  than  the  nerves,  they  become  converted  promptly  into 
fat  by  immersion  in  water. 

§  804.  The  ganglions  of  the  first  sort  are  those  which  are 
found  in  the  course  and  at  a  small  distance  from  the  origin  of 
the  nerves  of  the  spinal  marrow.  There  are  thirty  of  them, 
on  each  side,  which  are  named  spinal;  one  upon  the  trigemini 
nerve,  which  is  called  Gasser's  ganglion;  one  or  two  upon  the 
par  vagum,  and  one  upon  the  glosso-pharyngeal.  The  spinal 
ganglions,  first  observed  by  Volcher  Goiter,  to  the  number  of 
thirty  on  each  side,  have  an  ovoid  or  olive  form.  They  be- 
long to  the  posterior  root  alone  of  the  spinal  nerves,  the  ante- 

*  Lassaigne,  in  the  Journal  de  Physiologic,  vol.  i. 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVES.         507 

rior  is  united  to  the  ganglion  only  by  loose  cellular  tissue. 
Haase  first  made  this  observation,  which  has  since  been  con- 
firmed by  Prochaska  and  Scarpa.  The  anatomists  who  pre- 
ceded them  thought  that  the  two  roots  of  the  nerve  concurred 
in  the  formation  of  the  ganglion. 

The  membrane  of  the  spinal  ganglions,  furnished  by  the 
dura  mater,  appears  more  firm,  more  dense,  and  more  solid 
than  that  of  the  other  ganglions.  The  ganglion  itself  is  so 
closely  enveloped,  that  it  appears  very  hard.  The  pulpy  sub- 
stance envelopes  the  medullary  filaments  more  loosely  than  in 
the  others,  and  is  more  distinct  and  more  easily  separable. 

The  medullary  fasciculi  having  entered  by  the  posterior  or 
internal  extremity  of  the  ganglion,  divide  into  three,  four,  or 
five  white  filaments.  They  diverge  at  first  from  each  other, 
then  converge  towards  the  other  extremity.  These  filaments 
unite  with  each  other,  so  that  each  departing  cord  is  formed  of 
filaments  which  probably  come  from  several  entering  cords. 
However,  the  number,  the  tenuity,  and  the  confusion  of  the 
filaments  are  not  very  great.  The  spinal  ganglions  have  a  sim- 
ple texture  compared  with  the  others. 

The  nervous  fasciculi,  collected  together  after  leaving  the 
ganglion,  unite  intimately,  at  the  distance  of  hardly  two  lines, 
with  those  of  the  anterior  root,  to  form  the  common  trunk  of 
the  spinal  nerves:  a  trunk  which  itself  has  only  a  length  of 
one  or  two  lines  before  dividing  into  the  anterior  and  posterior 
branches. 

The  common  trunk  of  each  spinal  nerve,  at  a  little  distance 
from  the  ganglion,  furnishes  a  simple  branch,  often  double, 
rarely  triple,  which  goes  towards  the  ganglion  near  the  sym- 
pathetic nervous  trunk,  and  joins  it  in  such  a  manner  as  to 
establish  the  most  intimate  connexion  between  the  nerves  of 
the  spinal  marrow,  the  spinal  marrow  itself,  and  the  great 
sympathetic  nerve.  Anatomists,  and  especially  physiologists, 
have  frequently  discussed  the  question,  whether  the  branch  of 
communication  comes  from  this  or  the  other  root.  I  have 
seen,  as  well  as  Scarpa  and  Wutzer,  that  the  simple  or  double 
branch  comes  from  the  common  inextricable  trunk,  and  that, 
when  it  can  be  traced,  it  is  found  to  come  from  both  roots. 


508  GENERAL  ANATOMY. 

This  communicating  branch,  similar  at  its  origin,  to  the  spinal 
nerves,  having  arrived  at  about  a  line  from  the  ganglions  of 
the  sympathetic  nerve,  reddens  and  takes  successively  the 
characters  of  this  nerve. 

The  ganglion  of  the  fifth  pair  of  nerves,  or  Gasser's  gan- 
glion, belongs  evidently  to  the  series  of  spinal  ganglions,  from 
which  it  differs  only  in  form.  The  white  nervous  fasciculi 
which  pass  beneath,  without  forming  a  part  of  it,  that  Paletta 
proposed  to  consider  as  particular  nerves,  resemble  entirely 
the  anterior  root  of  the  spinal  nerves. 

The  ganglions  of  the  par  vagum  and  of  the  glosso-phargu- 
geal  nerve  resemble  as  yet,  in  their  form  and  texture,  the 
spinal  ganglions. 

The  trunk  even  of  the  par  vagum  has  a  texture  altogether 
peculiar  and  different  from  the  other  nerves,  without  resulting 
however  from  a  linear  series  of  ganglions,  as  Reil  says.  It 
greatly  resembles  the  trunk  of  the  sympathetic  nerve. 

§  805.  The  second  sort  of  ganglions  comprehends  the  series 
of  three  cervical  ganglions,  of  twelve  thoracic,  of  five  lumbar, 
and  of  four  sacral,  belonging  on  each  side  to  the  trunk  of  the 
sympathetic  nerve.  The  opthalmic  ganglions,  spheno-pala- 
tine,  and  maxillary,  are  also  of  the  same  sort.  The  cardiac 
ganglion,  often  replaced  by  a  plexus,  must  be  joined  with 
them,  as  well  as  the  semi-lunar  or  cceliac  ganglions,  and  many 
others  placed  in  the  solar  plexus  and  its  divisions;  the  little 
coccygeal  ganglion,  which  is  found  sometimes  at  the  union  of 
the  two  sympathetic  nerves,  opposite  the  summit  of  the  sa- 
crum; and  the  little  palatine  ganglion,  which  exists  sometimes 
in  the  anterior  palatine  foramen;  finally  some  variable  gan- 
glions are  also  added,  which  are  sometimes  found  upon  the 
coats  of  the  arteries,  where  they  replace  the  plexuses,  as  the 
ganglion  of  the  anterior  communicating  artery  of  the  brain, 
that  of  the  cavernous  sinus,  that  of  the  deep  seated  temporal 
artery,  &c. 

All  these  ganglions  have  in  general  an  irregular  and  variable 
figure;  they  have  in  general  connexions  with  several  nervous 
trunks  or  branches.  The  direction  of  the  medullary  filaments 
which  traverse  them  is  very  complicated,  and  rarely  thin  fila- 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVES.         509 

ments  traverse  them  simply  from  one  side  to  the  other.  The 
pulpy  substance  of  these  ganglions  is  so  Strongly  united  with 
the  medullary  filaments,  that  it  is  very  difficult  to  separate 
them.  This  substance,  besides,  appears  to  differ  from  that  of 
the  other  ganglions:  it  is  harder,  more  close,  and  more  tena- 
cious. This  is  especially  remarkable  in  the  cceliac  ganglions 
and  in  those  of  their  plexuses.  The  membrane  of  the  gan- 
glions of  this  series  is  cellular  and  firm,  but  has  not  the  fibrous 
solidity  of  that  of  the  spinal  ganglions. 

§  806.  The  cords  and  the  nervous  branches,  in  a  word,  the 
nerves  which  unite  these  ganglions,  greatly  differ  from  those 
which  are  immediately  derived  from  the  spinal  narrow.  In- 
stead of  diminishing  like  these  last,  in  proportion  as  they  de- 
part from  their  origin,  or  from  their  central  extremity  they 
furnish  successive  divisions,  we  see  them  indifferently  dimi- 
nish or  increase,  or  not  change  their  size  in  departing  from 
the  ganglions.  The  ganglionary  nerves  have  less  power  of 
cohesion  and  more  fragility  than  the  others.  The  external 
envelope  of  the  ganglions  continues  upon  the  nerves  to  a  cer- 
tain distance;  beyond  the  point  where  this  communication 
ceases  to  be  apparent,  the  neurilema  appears  thinner  and  more 
intimately  united  with  the  medullary  substance  than  in  the 
other  nerves.  Their  internal  substance  results,  like  that  of 
the  ganglions,  from  medullary  filaments,  and  pulpy,  gray  and 
reddish  substance, that  can  be  hardly  separated  from  them;  the 
filaments,  or  the  branches  united  to  form  a  cord,  are  them- 
selves hardly  separable;  the  ganglionary  nerves,  finally,  seem 
to  be  formed  of  the  same  substances  as  the  ganglions,  these 
being  only  elongated  into  cords.  However,  the  nerves  of 
the  ganglions  are  not  all  absolutely  similar:  those  which  unite 
the  spinal  ganglions  to  those  of  the  sympathetic  nerve,  and 
the  splanchnic  nerves,  which  go  from  the  thoracic  ganglions 
of  the  sympathetic  to  the  coeliac  ganglions,  seem  intermediate, 
by  their  white  colour,  their  cylindrical  form,  their  fibrous 
composition,  their  firmness  and  tenacity,  between  the  nerves 
of  the  spinal  marrow  and  the  reddish  gray,  flattened,  irregu- 
lar, pulpy;  soft  and  fragile  nerves  of  the  sympathetic.  Scarpa 
pretends  that  the  sympathetic  nerves  may  be  anatyzed  by 
anatomy,  aud  reduced  into  filaments  like  the  others.  I  think 


510  GENERAL  ANATOMY. 

that  this  is  impossible,  especially  in  the  nerves  which  form 
the  mesenteric  or  intestinal  plexuses. 

§807.  The,  sympathetic  nerve,*  intercostal  or  trisplanch- 
nic,  is  a  nervous  and  ganglionary  cord,  extended  from  the 
head  to  the  pelvis,  connected,  by  anastomosing  branches  or 
roots,  with  all  the  spinal  nerves  and  the  trigemini,  and  fur- 
nishing numerous  branches  to  the  organs  of  the  splanchnic 
cavities  of  the  trunk. 

The  cephalic  extremity  of  this  nerve  penetrates  into  the 
cranium  by  the  carotid  canal  and  the  cavernous  sinus,  where 
it  forms  a  plexus  and  often  a  ganglion  upon  the  carotid  artery; 
it  sends  hence  anastomosing  filaments  to  the  nerve  of  the  sixth 
pair,  and  communicates  with  'the  inferior  filament  of  the  vi- 
dian;  it  sends  secondary  plexuses  upon  the  branches  of  the  in- 
ternal carotid  artery,  and  may  be  traced  to  a  little  solitary 
ganglion  placed  upon  the  anterior  communicating  artery  of 
the  brain. 

It  consists  then  of  three  cervical  ganglions,  twelve  thoracic, 
five  lumbar  and  four  sacral,  and  of  their  cords  of  communica- 
tion placed  on  each  side  of  the  anterior  face  of  the  vertebral 
column. 

Throughout  the  whole  length  of  the  nerve,  each  ganglion 
presents  external  anastomosing  filaments  or  roots,  and  internal 
filaments  or  branches. 

In  this  respect,  the  sympathetic  nerve  may  be  compared  to 
a  subterraneous  stem,  or  an  articulated  rhizoma,  which,  at 
each  joint,presents  on  one  side  roots, and  on  the  other  branches, 
both  of  which  depart  at  right  angles,  or  at  least  at  a  very  large 
angle. 

The  branches  of  the  great  sympathetic  distribute  themselves 
to  the  organs  situated  in  the  face,  neck,  breast,  the  abdomen 
properly  so  called,  and  in  the  pelvis. 

The  pelvic  extremity  of  the  sympathetic  nerve  consists  of  a 

*  Walter,  tabulae,  nervorum  thorocis  ct  obdominis.  Berol.  1783. — H.  A. 
Wrisberg,  de  nervis  arterios  venasque  comitantilus. — De  Nervis  pharyngeis. 
— J)c  Ganglio  pkxuque  similunari. — Jh  Nervis  viscerum  abdominalium,  etc., 
in  Comment.  Getting. — Chaussier,  Table  synoptique  du  nerf  trispktnchnique. 
— Lobstein,  De  ncrvi  sympathetid  humani  fabrica,  usu  et  morbis.  Paris., 
1823-4,  cum  tabulis. 


ON  THE  GANGLIONS  AND  SYMPATHTIC  NERVE.  511 

little  ganglion  or  arch,  in  which  the  two  nerves  unite,  and 
which  furnish  some  delicate  filaments  to  the  environs  of  the 
anus. 

The  internal  branches  of  the  sympathetic  nerve  are  distri- 
buted, some  directly  upon  the  arteries,  and  form  plexuses,  the 
others,  in  much  greater  number,  reach  the  median  line,  and 
form  there,  in  uniting  to  those  of  the  opposite  side,  median 
plexuses  or  ganglions  (the  cardiac  and  creliac),  which  commu- 
nicate with  the  branches  of  the  pneumo-gastric  nerve,  which 
furnish  secondary  plexuses  or  ganglions,  and  terminate  in  the 
heart,  the  aorta,  the  digestive  canal,  the  urinary  and  genital 
organs,  but  especially  in  the  arteries  of  these  organs. 

§  808.  Rare  interruptions, -and  perhaps  not  well  observed, 
in  the  trunk  of  the  sympathetic  nerve,  have  induced  some 
anatomists  to  regard- the  existence  of  this  trunk  as  a  circum- 
stance of  little  importance.  There  is  exaggeration  in  this 
opinion.  However,  its  roots  are  very  certainly  in  the  spinal 
nerves,  and  not  in  the  vidian  nerve  and  the  sixth  pair. 

The  branches  of  the  sympathetic  nerve,  differ  not  only  from 
tfiose  of  the  other  nerves,  but  they  differ  very  much  from  each 
other:  each  ganglion  and  especially  each  plexus  of  branches 
has  its  proper  or  peculiar  character. 

The  sympathetic  nerve  has  been  considered,  by  Scemmer- 
ing  especially,  as  the  nerve  of  the  arteries:  in  truth  the  arteries 
receive  many  branches  from  it;  but  the  muscular  tissue  of  the 
heart,  that  of  the  digestive  canal,  the  mucous  membrane  of  this 
canal  and  the  .urinary  and  genital  passages,  the  ligaments,  the 
bones  even  of  the  vertebral  column,  receive  filaments  from  it. 
It  is  remarkable  that  the  veins,  the  lymphatic  vessels  and 
glands  are  deprived  of  them,  as  well  as  the  serous  membranes. 
They  are  found,  on  the  contrary,  in  the  long  muscles  of  the 
neck,  in  the  intercostals,  and  the  diaphragm. 

§  809,  The  spinal  ganglions  with  their  nerves,  are  the  first 
parts  of  the  nervous  system  that  are  visible. 

The  ganglions  and  the  nervous  trunk  of  the  trisplanchnic 
are  apparent  in  the  foetus  after  the  third  month.  The  coeiiac 
ganglions  and  the  splanchnic  nerves,  which  are  in  a  manner 

their  roots,  develope  themselves  a  little  less  quickly  than  the 
66 


512  GENERAL  ANATOMY. 

cervical  ganglions  and  the  cardiac  nerves.     In  old  age  the  gan- 
glions are  paler  and  drier  than  in  the  adult  age. 

The  ganglions  and  cords  of  the  sympathetic  nerves  are  found 
in  foetuses  deprived  of  brain,  and  in  those  which  are  deprived 
of  brain  and  spinal  marrow. 

§  810.  The  vertebrate*  animals  alone  have  a  particular  nerv- 
ous system  for  the  organs  of  vegetative  functions. 

In  fishes  the  sympathetic  nerve  consists  of  a  very  fine 
thread,  with  few  or  no  ganglions. 

In  reptiles  it  is  more  distinct:  it  unites  together  the  inter- 
vertebral  nerves,  and  penetrates  into  the  cranium  united  with 
the  par  vagum. 

In  birds  it  penetrates  into  the  cranium  with  the  par  vagum 
and  the  glosso-pharyngeal ;  it  communicates  with  the  fifth  and 
sixth  pairs;  it  presents  in  the  neck  an  apparent  interruption, 
arising  from  its  being  contained  in  the  .vertebral  canal:  it  is 
very  distinct  and.ganglionary  in  the  thorax,  and  is  prolonged 
even  unto-  the  caudal  vertebrae. 

in  the  mammalia  the  sympathetic  nerve  does  not  differ  much 
from  that  of  man. 

Meckel  and  Weber  have  remarked  that  the  sympathetic 
nerve  is  so  much  the  smaller,  relative  to  the  body,  as  the  -ani- 
mal is  farther  removed  from  man.  A  second  general  observa- 
tion is  that  the  sympathetic  nerve  and  the  par  vagum  are  in  an 
inverse  relation  with  respect  to  their  development;  so  that 
they  mutually  supply  the  place  of  each  other,  in  the  vegeta- 
tive life  to  which  they  both  belong.  It  is  nepessary  also  to 
remark,  that  the  sympathetic  nerve  is  developed  in  all  animals 
in  proportion  to  their  circulatory  apparatus,  to  which  it  in 
great  part  belongs. 

§  812.  The  ganglionary  nervous  system,  which  exists  in  all 
animals,  which,  in  the  vertebrata,  forms  a  system  apart,  in 
connexion  with  the  nervous  centre  whose  development  it  pre- 
cedes^  which  preserves  on  one  part  the  stale  of  dissemination 
that  the  nervous  system  of  the  invertebrata  presents,  and 
which  forms  also  some  principal  centres,  as  the  cardiac  plexus, 

*  Weber,  Jinatomia  compar.  nervi  sympath.;  Lips.,  1817. 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVE.         513 

and  especially  the  ganglions,  and  the  creliac  or  solar  plexus, 
which  has  been  called  the  abdominal  or  epigastric  brain,  should 
have  a  great  importance  in  the  organization.  But  before  ex- 
plaining the  functions  of  the  sympathetic  nerve,  it  is  necessary 
to  examine  tfcat  of  the  ganglions. 

§813.  Willis  had,  with  respect  to  the  ganglions  and  sympa- 
thetic nerve,  an  idea  similar  enough  to  that  which  now 
prevails:  he  considered  the  ganglions  as  the  diverticula  of  the 
spirits,  and  the  sympathetic. nerve  as  placed  between  the  cere- 
bral conceptions  and  the  precordial  affections,  between  the  ac-« 
tions  and  the  passions,  in  such  a  manner  as  to  establish  a  con- 
sent between  the  parts. 

Vieussens  considers  also  the  intercostal  nerve  as  a  sympa- 
thetic medium  between  the  brain  and  the  viscera  of  the  two 
other  cavities;  he  places  in  the  ganglions,  which  he  calls 
plexuses,  a  centre  of  muscular  and  fermentative  action.  Lan- 
cisi  also  regarded  the  ganglions  as  centres  of  impulse  which  he 
compared  to  the  heart. 

.  Winslow,  who  first  employed  the  name  of  sympathetic 
nerve,  regarded  the  ganglions  as  centres  of  origin,  true  little 
brains. 

Meckel  attributed  to  the  ganglions  the  use,  1st,  of  dividing 
the  nervous  branches  into  lesser  ramifications,  and  these  into 
ents;  2d,  of  making  the  branches  depart  in  different  di- 
rections to  distant  places;  3d,  of  uniting  several  branches  into 
a  single  cord. 

Zinn  holds  the  same  opinipn,  adding  that  the  branches  from 
different  points  uniting  in  a  ganglion,  are  more  intimately 
mixed  than  in  a  plexus. 

Johnstone  regarded  the  ganglions  as  brains  capable  of  de- 
veloping and  communicating  the  nervous  power,  as  the  origin 
of  the  involuntary  nerves,  and  as- proper  to  break  the  influence 
of  the  will  upon  the  organs  of  involuntary  motion,  such  as  the 
heart. 

Haase,  who  has  assimilated  the  ganglions  to  the  plexus,  has 
controverted  the  opinion  of  Johnstone  with  these  two  argu- 
ments: that  the  voluntary  muscles  receive  nerves  from  the  spi- 


514  GENERAL  ANATOMY. 

nal  ganglions,  and  that  the  involuntary  organs,  as  the  stomach, 
receive  them  from  the  par%a'gum. 

Scarpa  adopts  an  opinion  similar  to  that  of  Meckel  and 
Zinn:  according  to  him  the  use  of  the  ganglions  is  to  mix 
and  to  unite  anew  the  nervous  filaments;  according  to  him  the 
nerves  of  the  viscera  emanate  directly  from  the  spinal  nerves, 
and  from  the  fifth  and  sixth  pairs,  and  are  only  collected  to- 
gether in  the  ganglions. 

All  these  opinions,  as  we  see,  may  be  referred  to  two. 
•Some  as  Meckel,  Zinn,  Haase,  Scarpa,  and  more  recently, 
Legallois,  have  seen  in  the  ganglions,  only  a  particular  ar- 
rangement, an  anatomical  disposition  of  the  nervous  filaments; 
the  others,  as  Winslow,  Johnstone,  Lecat,  Petit,  Metzger, 
&c.,  have  regarded  the  ganglions  as  points  of  origin,  and  es- 
pecially as  centres  of  nervous  action.  No  one  has  defended 
this  last  idea  with  more  warmth  and  talent  than  Bichat.  Reil, 
Autenreith,  Wutzer,  Broussais,  and  many  others,  have  added 
new  arguments  to  those  of  our  celebrated  author,  whose  opin- 
ion they  have  nearly  embraced. 

§  814.  Bichat  regards  the  organic  nervous  system  as  result- 
,  ing  essentially  from  numerous  centres  or  from  ganglions  united 
together  by  filaments,  and  the  sympathetic  nervous  trunk  it- 
self as  a  series  of  ganglions  and  anastomosing  filaments.  Bi- 
chat has  perhaps  given  to  ganglions  an  exaggerated  import^ 
ance;  but  certainly  he  has  not  granted  to  their  ensemble,  their 
reunion,  all  the  importance  which  it  merits. 

According  to  Reil,  the  sympathetic  nerve  constitutes  a  pe- 
culiar system,  which  he  calls  ganglionary  system;  he  calls  it 
also  the  vegetative  nervous  system.  In  the  vertebrate  animals 
it  is  united  to  the  cerebral  or  animal  system,  but  if  does  not 
emanate  from  it.  This  system,  instead  of  having  a  single  cen- 
tre where  the  roots  are  implanted,  has  several -foci  of  action: 
1st.  It  consists  of  plexuses  or  net  work  placed  around  the  arte- 
ries, about  twelve  in  number;  among  them,  a  principal  one, 
the  epigastric,  furnished  with  ganglions,  and  forming  second- 
ary plexuses,  is  a  sort  of  centre  or  brain.  2d.  These  plexuses 
are  connected  with  the  cerebro-spinal  system  by  branches  and 
conducting  plexuses;  the  two  trunks  united  below,  before  the 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVE.  515 

coccix,  and  above  by  the  fifth  and  sixth  pairs  and  by  the  brain, 
constitute  an  elliptic  periphery  which  embraces  all  the  system 
of  ganglions  and  plexuses,  and  into  which  several  cerebral 
nerves  penetrate,  particularly  the  eight  pair.  3d.  The  branch- 
es or  conducting  plexuses  would  transmit  sensation  and  voli- 
tion, if  they  were  perfect  conductors;  but  they -may  be  consid- 
ered as  semi-conductors,  and  theganglio'ns  as  isolating  bodies. 

There  results  from  this  two  nervous  systems  and  two  spheres 
of  nervous  activity:  1st,  the  animal  sphere,  in  which  the  im- 
pressions are  perceived,  where  the  volitions  determine  motion; 
2d,  the  vegetative  sphere,  where  the  nervous  activity  is  distri- 
buted slowly,  continually,  and  obscurely.  In  this  system,  the 
impressions  determine  motion,  without  being  propagated  to 
the  animal  centre.  In  the  state  of  disease,  however,  the  com- 
municating cords  and  plexuses  become  conductors,  the  gan- 
glions cease  to  be  .isolating,  the  impressions  are  perceived, 
and  the  motions  are  influenced  by  the  animal  centre. 

According  to  Reil  also,  in  the  magnetic  sleep,  the  separa- 
tion of  the  two  nervous  centres  disappears,  and  the  epigastric 
nervous  centre,  the  centre  of  the  vegetative  sphere,  becomes 
a  distinct  sense. 

Autenreith  considers  the  sympathetic  nerve  as  arising  from 
the  brain  and  spinal  marrow,  but  becoming  more  and  more 
independent  in  proportion  as  it  is  separated  by  plexuses  and 
ganglions,  the  reddish  or  grayish  substance  of  the  sympathetic 
nerves  conducting  impressions  and  irritations  with  more  diffi- 
culty than  the  white. 

Weber  has  collected  together  many  anatomical  and  physio- 
logical arguments,  to  demonstrate  that  the  sympathetic  nerve 
constitutes  a  particular  system,  which,  independent  of  the 
brain,  has  its  centre  within  itself. 

Wutzer  has  observed;  as  well  as  Bichat  and  others,  that  the 
mechanical  irritation  of  the  sympathetic  nerve  does  not  pro- 
duce any  appreciable  effect;  whilst  a  more  powerful  irritant, 
as  galvanism,  determines  pains  and  convulsions. 

Broussais  considers  also  the  intercostal  nerve  as  a  peculiar 
system,  a  particular  sensitive  centre,  which  transmits  impres- 
sions to  the  animal  sensorium,  and  consequently  determina- 


516  GENERAL  ANATOMY. 

tions  to  the  voluntary  muscles.  In  the  foetus  it  acts  alone,  di- 
rects the  secretory  and  nutritive  organs,  excites  the  energy  of 
the  heart,  extends  its  action  to  the  animal  centre,  and  deter- 
mines automatic  movements.  In  anencephalous  and  amyeles 
foetuses,  it  excites  muscular  movements  by  its  action  upon  the 
spinal  nerves.  •  After  birth,  it  acts  upon  the  nervous  centre, 
transmitting  Jo  it  the  internal  sensations,  and  establishes  thus, 
between  the  brain  and  the  viscera  of  the  two  other  cavities,  a 
connexion  fertile  in  phenomena.  At  all  times  it  rules  the  ac- 
tion of  the  capillary  vessels,  and  directs  nutrition  through  the 
intermedium  of  the  formative  or  plastic  power,  which-this  in- 
genious writer  calls  vital  chemistry. 

§  815.  Almost  all  these  opinions,  which  consist  in  consider- 
ing the  system  of  ganglions  as  an  independent  system,  err  in 
being  too  absolute,  as  well  as  those  which  consider  in  the  gan- 
glions only  a  purely  anatomical  arrangement.  The  system  of 
ganglions  ought  to  bq  considered  at  the  same  time  as  a  system 
separate  or  united,  independent  or  dependent,  according  to 
different  circumstances  for  the  most  part  already  indicated. 

The  functions  of  the  ganglions  appear  to  be  to  diminish  or 
to  arrest  the  influence  of  the  nervous  centre  upon  the  gan- 
glionary  nerves,  to  diminish  or  to  hinder  the  transmission  of 
impressions  to  the  centre;  so  that  by  the  action  of  the  gangli- 
ons, the  vegetative  nervous  system  is  separated  from  the  ani- 
mal system.  ' 

The  ganglions  appear  besides  to  collect,  to  coerce  the  nerv- 
ous power  which  they  draw  from  the  spinal  marrow,  to  devel- 
ope  it  by  themselves,  to  communicate  it  conveniently  to  the 
nerves  and  to  the  organs  where. they  terminate. 

The  ganglions  exercise  different  functions  according  to  the 
diversity  of  their  texture. 

These  differences  consist  in,  lstrthe  mixture  more  or  less 
intimate  of  the  medullary  fibres;  2d,  the  diversity  of  the  se- 
condary substance;  3d,  the  differences  in  the  exterior  mem- 
brane, more  or  less  compact,  more  or  less  tense;  but,  it  is  in  . 
the  ganglions  of  the  sympathetic  nerve  that  we  observe  the 
greatest  intricacy  and  blending  of  the  medullary  filaments, 
the  tenacity  and  most  intimate  union  of  the  secondary  sub- 


ON  THE  GANGLIONS  AND  SYMPATHETIC  NERVE.  517 

stance,  and  a  membrane  or  capsule  tolerably  firm  and  very 
adherent  to  the  interior  substance.  In  the  spinal  ganglions, 
on. the  contrary,  the  medullary  filaments  are  straight,  unmix- 
ed, and  the  secondary  substance  is  coarse,  loose,  and  very  dis- 
tinct from  tne  filaments:  these  ganglions  also  are  regarded  as 
less  perfect  than  the  others;  Pfeffinger  also  thinks  that  they 
ought  to  be  excluded  from  this  class  of  organs.  The  function 
of  these  last  ganglions  remains  otherwise  very  doubtful.  It 
does  not  appear,  in  effect,  that  they  diminish  the  nervous  com- 
munication; neither  can  they  be  considered  as  the  origins  of 
the  common  motory  and  sensitive  nerves,  for  the  anterior  root 
of  the  spinal  nerves  is  distinct  from  them. 

§  816.  The  uses  of  the  ganglionary  nervous  cords  are  to 
conduct  the  nervous  influence;  but  they  are  conductors,  a  lit- 
tle different  from  the  other  nerves,  from  which  they  differ  by 
approximating  to  the  ganglions:  they  are  imperfect  conduct- 
ors. Mechanical  or  chemical  irritations  do  not  traverse  them; 
but  galvanic  irritation  is  conducted  by  them,  and  determines 
either  sensations  or  contractions.  It  is  the  same  with  morbid 
irritations,  as  irritations  of  the  intestines,  ureters,  &c.  which 
are  perceived. 

The  functions  of  the  sympathetic  nerve  are  to  direct  nutri- 
tion and  the  secretions;  to  distribute  the  nervous  agent  to  the 
heart,  the  digestive  canal,  and  the  urinary  and  genital  organs;' 
to  establish  a  sympathetic  connexion  between  all  the  principal 
organs.  It  fulfils  these  different  functions  without  the  influ- 
ence of  the  will  and  without  consciousness  of  impressions,  the 
ganglions  perfbrming  at  the  same  time  the  office  of  slight  li- 
gatures, which  moderate  the  transmission  of  the  nervous  influ- 
ence, and  of  parti c^r  centres  of  activity,  which  augment  and 
modify  its  distribution. 

This  nerve  forms  thus  a  particular  system  in  the  general 
system;  it  has  a  'sphere  of  peculiar  action  enclosed  within  the 
general  sphere.  Both  nervou|  systems  have  intimate  connex- 
ions; they  influence  each  other  reciprocally,  especially  in  a 
morbid  state. 

§  817.  Lobstein  has  collected  several  very  curious  facts  re- 
lative to  the  morbid  alterations  of  the  ganglions  and  sympathet- 


518  GENERAL  ANATOMY. 

ic  nerves:  he  has  observed  the  inflammation  of  the  semi-lunar 
or  coeliac  ganglions,  in  cases  of  chronic  abdominal  neuropathy, 
hoopi  ng-cough,  and  tetanus;  he  has  also  observed  in  several  cases 
the  inflammation  of  the  cardiac  and  pulmonary  nerves.  Au- 
tenreith  has  also  observed  in  hooping-cough  the  inflammation 
of  the  par  vagum,  sympathetic,  and  cardiac.  Duncan  has  seen 
in  a  case  of  diabetes  the  abdominal  portion  of  the  sympathetic 
nerve  three  or  four  times  larger  than  usual. 

The  sympathetic  nerves  are,  like  the  others,  augmented  in 
volume  in  hypertrophies,  diminished,  on  the  contrary,  in  sim- 
ple atrophies,  as  well  as  in  those  which  result  from  an  acci- 
dental production  infiltrated  into  the  tissue  of  an  organ. 

Many  abdominal  and  thoracic  diseases  seem  besides  to  de- 
pend on  an  irregular  action  of  the  sympathetic  nerve;  and 
others,  very  numerous  also,  on  the  anormal  action  of  this  nerve 
upon  the  cerebral  nervous  centre. 


OF  ACCIDENTAL  PRODUCTIONS.  519 


CHAPTER  XI. 


OF  ACCIDENTAL  PRODUCTIONS. 

§818.  The  productions  which  occur  accidentally  in  the  hu- 
man organization  are  humours,  concretions,  tissues,  and  living 
animals. 

These  objects  do  not  form  a  part  of  the  healthy  or  regular 
organization:  they  belong  only  to  morbid  anatomy.  Their 
description,  or  at  least  their  summary  indication,  here  has  for 
its  object  to  complete  what  has  been  said,  under  the  head  of 
each  tissue  in  particular,  upon  the  alterations  and  productions 
which  are  peculiar  to  it.  The  productions  which  are  under 
consideration  in  this  chapter,  are  common  to  several  parts  or 
to  the  tofality  of  the  organization. 

The  knowledge  of  the  accidental  productions  and  alterations 
is  very  important  to  'the  pathological  anatomist;  for,  on  the 
one  hand,  this  knowledge  is  the  basis  of  pathology;  and  on 
the  other  hand,  anatomy  being  rarely  studied  upon  healthy 
subjects,  but  generally  upon  the  bodies  of  diseased  individu- 
als, the  anatomist  meets  at  every  instant',  in  his  researches, 
with  alterations  of  organization  and  accidental  productions. 


SECTION  I. 

OF  ACCIDENTAL  HUMOURS. 

§  819.  The  natural  humours  may  be  altered  in  their  quan- 
tity or  quality;  soTne  of  these  alterations  have  been  indicated. 
We  sometimes  find  besides  humours  altogether  different  from 
67 


520  GENERAL  ANATOMY. 

the  first.  Among  these,  pus  is  the  only  one  which  is  suffi- 
ciently well  known  to  be  described. 

§  820.  Pus*  is  an  accidental  humour  resulting  from  a  mor- 
bid secretion, -which  is  called  suppuration.  Pus  is  composed 
of  microscopic  globules,  similar  to  those  of  the  blood,  disco- 
vered by  Home,  floating  in  a  fluid  coagulable  by  the  solution 
of  muriate  of  ammonia. 

It  is  of  a  white  or  yellowish  colour,  opake,  and  of  the  con- 
sistence of  cream.  Its  consistence  and  its  colour  depend  upon 
ttoe  proportion  of  globules  to  the  fluid  part.  It  is  heavier 
than  water.  It  has  a  taste  slightly  saline,  constant,  and  a  pe- 
culiar weak  odour,  a  little  variable. 

Pus  sinks  in  water,  while  mucus  floats.  By  agitation  pus 
becomes  diluted,  mixes  with  the  water,  and  whitens  it  uni- 
formly; mucus,  on  the  contrary,  remains  in  distinct  flocculi. 
Pus  coagulates  by  heat,  acids,  and  alcohol;  alkalies  render  it 
viscous,  thready,  and  dissolve  it.  It  is  composed,  according 
to  Schwilgue,  of  albumen  in  a  particular  state,  of  extractive 
matter,  of  a  fatty  matter,  of  soda,  of  muriate  of  soda,  of  phos- 
phate of  lime,  and  of  other  salts.  It  resembles  much  the  se- 
rum of  the  blood,  from  which  it  appears  to  differ  orjy  by  the 
state  of  the  albumen  and  of  the  extractive  matter.  •  Mucus  be- 
comes diluted  in  water,  dissolves  by  the.  addition  of  sulphuric 
acid,  while  pus  does  not.  A  solution  of  caustic  alkali  dissolves 
at  the  same  time  pus  and  mucus,  and  by  the  addition  of  water 
the  pus  is  precipitated  alone.  These  chemjcal  characters,  and 
others  of  the  same  Jdnd,  are  not  as  certain  as  the  action  of  wa- 
ter alone,  and  especially  as  microscopic  observation. 

*  "C.  Darwin,  Experiments  establishing  the  criterion  between  irmcagi- 
nous  and  purulent  matter;  Lig-htfield,  1780. — Brugrnans,  Dissertatio  de  pyo- 
genia;  Groningse,  1785. — E.  Home,  on  the  properties  of  pus;  London,  1789. 
— Grasmeyer,  Mhandlung  von  dem  eiter,  &c.;  Getting",  1790. — Schwilgue, 
Mtmoire  intdit  sur  lepus,  analyst  dans  la  Nosogr.  Philos.,  vol.  ii. — G.  Pear- 
son, on  expectorated  matter;  .in  Phil.  Trans.,  1*809. — Idem,  Observations 
and  experiments  on  pus;  ibid.,  1810. — Rizetti,  De phtJiisi pulmonali  specim. 
chim.  med.,-  in  Mem.  de  Turin,  vol.  ii.  et  iii. -»-Rossi  and  Michelotti,  Analyse 
premiere  du pus,-  ibid.,  vol.  iii. — E.  Home,  On  the.oonversion  of  pus  into 
granulations  or  new  flesh;  in  Phil.  Trans.,  1819. 


OP  ACCIDENTAL  HUMOURS.  521 

Pus  does  not  always  present  precisely  the  same  physical 
qualities  and  the  same  chemical  properties.  It  can  be  distin- 
guished mto  creamy  pus,  homogeneous,  commonly  called  most 
laudable;  into  serous  pus,  sanious,  or  purulent  serosity,  into 
glareous  pus  or  puriform  mucus;  into  curdled  or  clotted  pus; 
into  concrete  or  plastic  pus.  Besides,  pus  may  be  mixed  with 
blood,  serosity,  excrementitious  matters,  putrid  matter,  acci- 
dental tissues,  calculi,  virulent  matter,-  &c. 

In  all  these  cases  it  is  composed,  according  to  Pearson,  of  a 
white,  opaque,  and  slightly  soluble  animal  oxide,  of  a  limpid 
fluid,  analogous  to  the  serum  of  the  blood,  which  holds  the 
animal  oxide  in  suspension,  but  not  in  a  state  of  solution;  and 
of  an  innumerable  quantity  of  microscopic  globules.  The  dif- 
ferences which  it  presents  depend  on  the  different  proportions 
in  which  these  essential  materials  are  found,  as  well  as  the 
substances  which  may  be  found  there  accidentally. 

§  821.  Pus  may  be  formed  in  the  greater  part  of  the  organs. 

The  tissue  in  which  suppuration  is  most  frequent  and  seems 
the  most  easy,  is  the  mucous  membrane.  Some  hours  after 
the  application  of  an  irritating  cause,  the  physical  and  chemi- 
cal properties  of  mucus  are  seen  to  change  insensibly  into  those 
of  pus.  When  the  irritation  diminishes  and  ceases,  the  pro- 
perties-of  pus  are  seen  to  change  inversely  into  mucus.  The 
suppuration  of  the  mucous  membrane  is  accompanied  with  a 
slight  degree  of  redness  and  swelling,  and  very  rarely  with 
ulceration. 

The  skin  suppurates  easily  whenever  it  is  irritated  and  the 
epidermis  removed.  This  may  continue  indefinitely,  if  the 
irritation  is  continued,  or  frequently  renewed;  the  skin  then 
takes  on  the  aspect  of  an  inflamed  mucous  membrane. 

The  cellular  tissue  being  exposed  by  the  removal  of  the 
skin,  the  hemorrhage  stops;  then  flows  serosity,  which  by  de- 
grees takes  the  character  of  pus.  At  the  same  time  the  wound- 
ed surface  covers  itself  with  a  layer  of  organizable  matter, 
which  becomes  vascular  and  covered  with  granulations. 

The  cellular  tissue  being  irritated  by  a  foreign  body  or  by 
an  unknown  cause  (spina  helmontii)  inflames;  pus  forms  in 
the  centre  of  the  phlegmon :  this  pus  is  enclosed  in  a  mem- 


522  GENERAL  ANATOMY. 

brane  of  a  new  formation,  more  or  less  distinct,  more  or  less 
vascular,  according  to  its  age;  the  surrounding  cellular  tissue, 
inflamed  and  very  vascular,  has  lost  its  permeability  by  the 
interstitial  deposition  of  organizable  matter. 

The  serous  membranes,  when  they  suppurate,  present  ana- 
logous changes;  they  become  very  vascular  and  take  at  length 
the  appearance  of  mucous  membranes. 

§  822.  Boerhaave  attributed  the  origin  of  pus  to  the  meeting 
of  inflamed  organs;  Pringle  and  Gaber  attributed  it  to  a  change 
in  the  serum  of  the  blood;  these  two  opinions,  differently  mo- 
dified and  combined,  have  been  for  a  long  time  and  generally 
adopted. 

The  idea  that  pus  is  formed  in  vessels,  and  that  it  departs 
from^them  by  a  secretory  action  of  these  organs,  was  first  in- 
dicated by  Dr.  Sympson,  then  by  Dehaen,  and  afterwards-by 
Dr.  Morgan,  of.  Philadelphia.  Hunter  and  Brugmans  have 
embraced  and  developed  this  doctrine,  which  is  now  general- 
ly adopted. 

Suppuration  is  a  morbid  secretion.  This  secretion  is  al- 
ways preceded  and  determined  by  inflammation;  but  the  in- 
flammation is  more  or  less  evident.  Dehaen  himself,  who 
expressly  admits  suppuration  without  previous  inflammation, 
evidently  means  to  speak  only  of  inflammation  with  ulcera- 
tion:  in  fact,  we  now  well  know,  what  he  then  announced, 
that  suppuration  might  take  place  upon  surfaces  without  altera- 
tion; he  notices,  in  cases  of  suppuration  without  inflammation, 
plastic  productions  and  adherences  which  depend,  as  we  know, 
on  inflammation. 

In  scrofulous  constitutions  suppuration  is  often  preceded 
only  by  a  chronic  and  latent  inflammation,  but  which  does  not 
the  less  exist,  although  it  is  obscure. 

§  823.  Suppuration,  when  it  exists  for  a  long  time,  and  when 
it  takes  place  on  a  large  surface,  becomes,  by  its  association 
with  the  functions,  an  important  secretion;  thus  we  should 
not  lightly  establish  or  suppress  a  suppuration. 

Pus  is  sometimes  the  vehicle  of  virus  introduced  into  the 
organization;  it  is  considered  also,  in  some  cases,  as  the  vehi- 
cle of  the  cause  of  maladies  eliminated  by  the  organization. 


OF  STONY  CONCRETIONS.  523 

According  to  Sir  Ev.  Home,  pus  has  for  its  use  to  furnish, 
by  its  coagulation  on  the  surface  of  suppurating  wounds,  the 
materials  of  the  cicatrix,  that  is  to  say,  the  organizable  matter 
of  this  new  tegument. 


SECTION  II. 

OF  STONY  CONCRETIONS. 

§  824.  Concretions  or  calculi*  are  solid  bodies,  more  or  less 
hard,  wliich  form -in  the  humours  contained  in  the  cavities, 
the  reservoirs,  and  the  ducts  lined  with  the  mucous  mem- 
brane. This  formation  is  always  accompanied  by  a  change  of 
composition  more  or  less  evident  of  the  fluids  where  it  takes 
place. 

§825.  Intestinal  calculi  are  rare  in  the  human  species. 
These  calcul-i,  more  or  less  voluminous  and  numerous,  are 
round  or  ovoid,  yellow  or  brown:  their  specific  gravity  is  1.4. 
Their  nucleus  is  a  biliary  calculus,  hardened  faeces,  or  a  fo- 
reign body.  They  are  formed  of  layers,  and  composed  of 
earthy  substance,  especially  phosphate  of  lime,  and  a  little 
animal  substance. 

The  mucous  and  sebaceous  follicles  contain  sometimes  indu- 
rated or  more  or  less  concrete  masses. 

Several  instances  have  been  cited  of  little  calculi  of  phos- 
phate of  lime  and  animal  matter,  in  the  caruncula  lachryma- 
lis,  in  the  tonsils,  and  in  the  prostate. 

Stony  concretions  of  the  same  nature  have  been  found  some- 
times in  the  lachrymal  canal  and  sac,  in  the  salivary  glands 
and  their  ducts,  and  in  the  pancreas. 

§  826.  The  biliary  passagest  are  frequently  the  seat  of  cal- 

*  Walter,  de  concrementis  terrestribus.    Berol.,  1775. — Vicq.  d'Azyr,  Jlca- 
dem.  roy.  de  medicine,  ann.  1779. — Mosovius,  Dissert,  de  cakulorem  anima- 
lium,  corumque  imprimis  biliariorum  origine  et  natura.    Berolini,  1812.      * 
•  f  Soemmering,  de  Concrementis  biliariis  carp,  humani^   Traject.  ad  Moen., 
1795.— Thenard,  Mem.  de  la  Soc.  d'Arcueil,  vol.  i. 


524  GENERAL  ANATOMY. 

culi,  cholelithi.  They  are  found  most  often  in- 'the  gall  blad- 
der; sometimes  in  the  duct  us  choledochus  or  the  cystic,  or 
hepatic  ducts;  or  in  the  intestinal  canal,  and  rarely  in  the 
roots  of  the  hepatic  canal  within  the  liver.  The  number  and 
size  of  these  calculi  vary  extremely:  from  one  to  several  thou- 
sand have  been  found  in  the  same  gall  bladder,  from  the  size 
of  a  pullet's  egg  to  that  of  a  millet  seed;  their  colour  varies 
from  white  to  yellow,  brown,  and  black;  their  surface  is 
rounded  or  polyhedral,  polished  or  rugose;  their  consistence 
varies  much;  their  specific  gravity  is  from  0.20  to  0.35.  They 
are  divided,  according  to  Walter,  into  three  kinds:  striated  or 
radiated,  striati^  lamellated,  lamellati,  and  provided  with  a 
rind,  cordicati.  In  the  human  species  these  calculi  are* formed 
of  cholesterine,  of  the  yellow  matter  of  the  bile,  and  some- 
times of  a  little  picromel. 

Urinary  calculi,*  urolithi,  are  found  in  the  pelvis  of  the 
kidney,  in  the  ureter,  in  the  mouth  of  this  canal,  in  the  blad- 
der, in  the  urethra,  in  the  prepuce,  in  the  loculi  of  the  bladder, 
in  the  ducts  of  the  prostate,,  and  in  accidental  urinary  cavities 
and  passages. 

The  calculi  of  the  pelvis  and  calices  of  the  kidney,  mould 
themselves  in  these  cavities,  when  they  increase  in  this  place 
and  become  ramose  like  a  branch  of  coral. 

Calculi  of  the  bladder  are  the  most  common;  sometimes, 
and  it  is  so  ordinarily,  there  is  only  one  in  the  bladder,  some- 
times there  are  several;  more  than  a  hundred  have  been  seen. 
Their  size  and  their  weight  vary  from  that  of  a  grain  of  wheat 
to  that  of  an  infant's  head,  and  to  more  than  six  pounds  in 
weight.  Their  form  is  round,  obround,  tetrahedral,  cunei- 
form, or  cubic,  &c. 

Their  surface  is  smooth,  rugose,  or  mamillary;  their  colour 
apd  consistence  are  very  variable.  They  have  always  a  nu- 
cleus, formed,  either  of  a  gravel  stone  descended  from  the 
pelvis  of  the  kidney,' a  clot  of  blood,  a  flocculus  of  mucus,  or 
a  foreign  body. 


*Fourcroy  et  Vajiquelin,  Mem.  de  Pinst.  .Nat.,  torn.  iv. — Wollaston, 
Phibs.  Trans.,  ann.  1797,  &c.  • 


OF  ACCIDENTAL  TISSUES.  525 

They  are  sometimes  homogeneous,  frequently  formed  of 
superimposed  layers,  similar  or  different;  at  other  times  mix- 
ed or  heterogeneous,  and  without  layers. 

The  calculi  of  the  bladder  are  composed:  1st,  of  uric  acid; 
2d,  of  cystic.oxide;  3d,  of  phosphate  of  lime;  4th,  of  urate  of 
ammonia;  5th/  of  ammoniaco-magnesian  phosphate;  6th,  of 
oxalate  of  lime;  7th,  of  silex;  Sth,  of  carbonate  of  lime;  9th, 
of  xanthic  oxide;  10th,  of  fibrinous  matter;  llth,  of  mucus; 
and  12th,  of  phosphate  of  iron,  and  magnesia,  of  carbonate  of 
magnesia,  and  urate  of  soda.  These  substances  are  found  in 
calculi,  either  isolated  or  combined  by  two,  three,  four,  and 
five.  The  most  common  of  all  is  the  calculus  of  uric  acid; 
then  the  fusible  calculus,  composed  of  the  ammoniaco-magne- 
sian and  calcareous  phosphates;  then  the  mural  calculus,  com- 
. posed  of  oxalate  of  lime;  then  the  calculus  formed  of  distinct 
layers  of  uric  acid  and  of  oxalate  of  lime,  &c.  Silex  and  the 
cystic  oxide,  and  still  more  the  xanthic  oxide  and  fibrine,  are 
the  rarest  substances  in  urinary  calculi. 

§  828.  It  is  said  that  pisiform  calculou*  concretions  have 
been  found  in  the  spermatic  vesicles  and  ejaculatory  ducts. 

Similar  little  concretions  are  sometimes  found  also  in  the 
fallopian  tubes.  As  to  concretion^  in  the  uterus,  these  are  for 
the  most  part  ossified  fibrous  bodies.  However,  concretions 
of  phosphate  of  lime  have  been  found  in  this  organ  having  a 
foreign  body  for  a  nucleus. 

We  are  assured  that  calculous  concretions  have  been  found 
in  the  excretory  ducts  of  the  nipple. 


SECTION  III. 


OF  ACCIDENTAL  TISSUES. 

§  829.  Accidental  tissues*  are  new  organs  developed  in  the 
living  body. 

*  Laennec,  Cours  oral  de  medecine,  au  College  de  France,  annte  1820-1823. 


526  GENERAL  ANATOMY. 

These  tissues  may  be  divided  into  two  kinds:  1st,  tissues 
analogous  to  those  of  the'healthy  organization; 

2d.  Heterologous  tissues  or  tissues  without  analogy  in  the 
regular  organization. 

There  are  also  some  accidental  tissues,  intermediate,  so  to 
speak,  between  the  one  and  the  o^her,  analogous,  if  not  with 
any  thing  in  the  human  organization,  at  least  with  that  of 
other  animals. 

§  830.  These  different  kinds  of  tissues  are  sometimes  iso- 
lated, at  others,  and  frequently,  united  or  combined  with  each 
other.  They  are  even  often  united  with  accidental  humours, 
with  living  animals,  with  altered  humours  or  tissues,  &c. 

§831.  Among  anatomists  and  pathologists,  some  (Dupiiy- 
tren,  Cruveilhier,  &c.)  regard  accidental  tissues  as  the  result 
of  transformations  experienced  by  the  natural  tissues:  they  call 
the  analogous  accidental  tissues,  transformations  properly  so 
called,  and  heterologous  tissues,  degenerations;  others  (J. 
Hunter,  Abernethy,  Laennec,  &c.)  regard  them  as  new  or 
epigenetic  productions.  It  is  a  question  very  difficult  to  re- 
solve; however,  the  last  opinion  appears  to  us  the  most  con- 
formable to  observation.  •  ' 

§832.  True  transformations  are  very  rare,  and  take  place 
only  between  nearly  similar  tissues:  thus  the  cartilages  of  the 
larynx  change  into  bone;  the  mucous  membrane  exposed  to 
the  air  changes  into  skin,  as  the  skin  drawn  into  the  interior, 
by  a  cicatrix,  becomes  mucous  membrane,  &c.  It  is  thus  that 
we  see,  in  trees,  roots  change  into  branches,  and  reciprocally 
branches  into  roots.  But  most  of  the  pretended  transforma- 
tions are  only  productions:  thus  a  cicatrix  is  a  membrane  en- 
tirely new,  and  not  the  result  of  the  transformation  of  denuded 
tissues;  thus  cancer  of  the  neck  of  the  uterus,  is  the  result  of  a 
substance  of  new  formation  infiltrated  into  its  tissue,  which 
has  separated,  compressed  it,  and  brought  on  atrophy,  and  not 
the  result  of  a  degeneration  of  this  tissue. 


OF  HETEROLOGOUS  ACCIDENTAL  TISSUES.  527 

ARTICLE  I. 
OP  ANALOGOUS  ACCIDENTAL  TISSUES. 

§833.  These  tissues  resemble  more  or  less  perfectly  the 
tissues  of  the  healthy  man. 

They  are  alterable  like  the  natural  tissues,  and  even  more  so. 

These  tissues  are  of  two  sorts:  1st,  some  are  the  result  of 
the  adhesion  of  the  lips,  of  a  solution  of  continuity,  or  of  re- 
generation after  a  loss  of  substance;  2d,  the  others  are  a  result 
of  a  production  altogether  accidental.  Both  have  been  de- 
scribed under  the  head  of  each  tissue  (Chap.  \  to  x). 

§  834.  The  demi-analogous  tissues  are,  1st,  some  of  the 
above  tissues,  which  do  not  attain  a  perfect  degree  of  organi- 
zation: such  are  especially  cicatrices  or.  accidental  cutaneous 
productions,  the  production  of  the  white  compact  and  flaccid 
tissue,  demi-cartilaginous  productions,  earthy  and  stony  ossi- 
fications, imperfect  corneous  productions,  &c. ;  2d,  there  are 
also  the  pearly  production,  analogous  to  the  natatory  bladder 
of  fishes,  observed  in  the  walls  of  cysts ;  the  production  of 
fungus  in  laminae,  etc. 


ARTICLE  U. 
OF  HETEROLOGOUS  ACCIDENTAL  TISSUES. 

§  835.  Heterologous  accidental  tissues,  morbid,  or  without 
analogy  in  the  healthy  organization,  arc  numerous.  The  most 
common  and  best  characterized  are,  tubercles,  schirrus,  the 
encephaloid  tumours  and  melanosis;  some  others  of  more  rare 
occurrence  will  be  indicated  hereafter. 

§  836.  These  tissues  commence  probably  in  the  fluid  state; 
but  from  the  moment  they  are  perceptible  they  are  solid. 
They  remain  for  a  greater  o*  less  time  in  this  state,  which  is 
called  that  of  crudity  or  of  organization;  a  state  in  which  they 
may  be  compared  to  zoophytes,  in  which  they  present,  for  the 
most  part,  vessels,  and  are  injurious  only  mechanically*  They 

afterwards  soften j  decompose  and  liquify.     In  this  state,  which 
68 


528  GENERAL  ANATOMY. 

Bayle  compares  to  an  anticipated  death,  they  cause  pains  more 
or  less  sharp,  and  sometimes  none ;  they  irritate  and  inflame 
the  neighbouring  parts;  they  exercise  a  deleterious  action 
upon  the  organization,  and  particularly  upon  nutrition,  even 
upon  that  of  the  bones  ;  they  extend  and  multiply  then  more 
or  less  rapidly  in  the  organization. 

The  origin  and  cause  of  these  tissues  are  unknown.  They 
have  been  regarded  as  innate  or  hereditary;  as  resulting  from 
an  aberration  of  the  formative  action ;  as  organized  beings  de- 
veloping and  dying  prematurely  in  the  midst  of  the  organiza- 
tion ;  as  products,  results  of  inflammation  and  irritation,  &c. 
These  are  so  many  hypotheses  more  or  less  ingenious  and 
more  or  less  well  founded. 

These  tissues  exist  under  the  form  of  isolated  masses,  of  en- 
veloped masses,  of  infiltrations  in  the  tissue  of  organs,  &c. 

Sometimes  they  exist  separately,  sometimes  combined  with 
each  other  and  with  other  accidental  productions,  and  with  al- 
tered tissues  and  humours. 

I.    OF  TUBERCLES. 

§  837.  The  tubercle,  or  tubercles,  for  they  exist  almosjt  al- 
ways in  great  numbers,  constitute  the  most  common  morbid 
tissue.  They  are  called  also  scrofulous  tubercles,  because 
they  are  met  with  in  most  cases  of  scrofula. 

This  tissue  exists  under  the  form  of  isolated  or  enveloped 
masses,  and  under  that  of  infiltration. 

It  commences  by  the  gelatiniform  state;  but  this  state  is 
perceivable  only  when  the  tuberculous  substance  is  infiltrated. 

It  afterwards  enters  into  the  grayish,  transparent,  as  if  demi- 
cartilaginous  state:  this  is  the  first  distinct  period  of  isolated 
tubercles;  they  constitute  the  miliary  granulations  of  Bayle. 

These  grains  in  enlarging,  often  unite  in  a  mass;  th'ey  be- 
come opaque,  yellowish,  friable,  commencing  by  the  centre. 
The  same  change  of  colour  ana*  consistence  takes  place  in  the 
state  of  infiltration  ;  it  is  y.et  the  state  of  crudity. 

They  afterwards  soften  and  liquefy:  at  this  period,  or  even 
in  the  preceding  periods,  there  is  produced  much  new  tuber- 
culous substance,  e'ither4n  mass,  or  by  infiltration. 


*        OP  THE  ENCEPHALOID  TUMOUR.  529 

The  tuberculous  matter,  softened  more  or  less  completely, 
into  homogeneous  pus,  or  into  clotted  pus,  is  evacuated  by  an 
opening  in  the  skin  or  mucous  membrane;  it  is  perhaps  also 
sometimes  re-absorbed.  Sometimes  the  collection  remains  in- 
flamed, ulcerated  indefinitely;  at  others  it  contracts  and  be- 
comes obliterated ;  sometimes  the  membrane  of  new  formation 
which  lines  it  acquires  a  demi-mucous  or  demi-cartilaginous 
texture,  and  constitutes  a  permanent  dry  fistula ;  at  others, 
finally,  a  friable  matter  only  is  found,  probably  the  residue  of 
a  re-absorption,  the  tubercle  not  having  formed  an  abscess. 

Vessels  are  never  found  in  tuberculous  masses:  in  the  case 
of  tuberculous  infiltration,  the  vessels  being  compressed  and 
obliterated,  shortly  disappear.  The  masses  which  are  devel- 
oped slowly  have  a  soft  or  glutinous,  cellular,  cartilaginous, 
and  sometimes  even  osseous  envelope. 

The  tuberculous  tissue  is  found  in  all  the  organs,  and  espe- 
cially in  the  lungs;  in  the  natural  and  accidental  cellular  tissue, 
at  the  surface  of  serous  membranes,  but  especially  in  their 
false  membranes,  at  the  free  surface  of  the  mucous  membrane, 
and  especially  that  of  the  intestine,  in  the  lymphatic  ganglions, 
in  the  glands,  in  the  spleen,  in  the  bones,  in  the  muscular  tis- 
sue, in  that  of  the  heart,  in  the  encephalon  and  in  the  spinal 
marrow,  and  in  compound  tumours. 

This  morbid  tissue  has  been  observed  in  all  vertebrate'  ani- 
mals. 

II.      OF  THE  ENCEPHALOID   TUMOUR. 

§  838.  The  encephaloid  or  cerebriform  tissue  is  a  very  com- 
mon morbid  production:  it  has  been  confounded  under  the 
name  of  cancer  with  several  others,  and  especially  with  schir- 
rus.  Bayle  and  Laennec  were  the  first  who  gave  an  exact  de- 
scription of  it  It  is  the  medullary  cancer,  the  fungous  inflam- 
mation, the*  fungous  hematodes  of  some  English  writer. 

This  tissue  exists  under  the  form  of  denuded  or  enveloped 
masses,  and  also  under  that  of 'infiltration". 

In  the  state  of  crudity,  it  forms  masses  of  various  size;  each 
mass  is  lobed,  lobulated,  and  the  lobules  are  ordinarily  turned 


530  GENERAL  ANATOMY.  ' 

like  the  convolutions  of  the  brain.  This  tissue  is  then  firm, 
like  the  rind  of  bacon,  semi-transparent,  without  colour,  or 
whitish  or  grayish;  the  lobules  are  united  together  by  an  im- 
perfect cellular  tissue,  of  extreme  softness;  they  become  con- 
founded in  proportion  as  the  mass  is  developed.  Numerous 
vessels,  very  fine,  and  with  very  weak  walls,  are  ramified  in 
this  cellular  tissue  and  in  the  encephaloid  substance  itself. 

When  the  development  is  complete,  the  encephaloid  tumour 
is  of  a  white  colour;  violaceous  or  rose-coloured  in  different 
places,  either  in  tints  or  points.  This  morbid  tissue  is  then 
very  analogous  to  the  cerebral  tissue,  but  more  loose,  and  less 
tenacious.  It  presents  otherwise  different  degrees  of  consist- 
ence in  the  same  mass;  degrees  comparable  to  those  of  differ- 
ent parts  of  the  encephalon. 

The  encephaloid  masses  which  are  not  enveloped  by  a  dis- 
tinct membrane,  are  so  by  a  layer  of  soft  cellular  tissue;  others 
have  a  demi-cartilaginous  envelope,  lined,  on  the  interior, 
with  soft  and  vascular  cellular  tissue  like  the  first.  Sometimes 
the  cyst  is  incomplete  in  its  development;  in  all  cases  it  ap- 
pears to  be  posterior  in  its  formation  to  the  substance  which  it 
contains. 

The  cerebriform  infiltration  is  very  common,  especially  in 
the  tissue  of  the  neck  of  the  uterus;  in  this  state  the  period  of 
crudity  is  very  short. 

The  softening  of  this  tissue  gives  place  to  a  pultaceous  mat- 
ter of  a  rose  colour.  Sometimes  then,  the  vessels  giving  way, 
sanguineous  infiltration  takes  place  in  the  cellular  tissue,  or 
effusions  similar  to  apoplexy  in  the  softened  substance:  the 
blood  then  concretes,  and  is  in  part  re-absorbed;  sometimes 
even  a  membrane  like  a  cyst  is  formed  about  the  blood;  some- 
times serous  infiltrations  take  place  in  the  surrounding  cellu- 
lar tissue,  or  serous  effusions  in  the  substance  itself,  which  is 
then  fluid  like  the  white  softening  of  the  brain. 

Whatever  may  be  the  resemblance,  in  effect  very  great,  be- 
tween the  morbid  tissue  of  which  we  speak,  and  the  substance 
of  the  brain,  there  is  no  identity;  and  we  can  not  admit  the 
opinion  of  Maunoir,  who  regards  this  tissue  as  the  product  of 
an  effusion  of  nervous  matter. 


OF  SCHIRRUS.  531 

When  the  softening  is  exterior  or  in  contact  with  the  air, 
the  surface  is  gray,  greenish,  fetid,  inflamed;  sometimes  it  de- 
stroys itself  by  falling  into  putrefaction. 

This  tissue,  multiplies  itself  in  the  organization,  less,  how- 
ever, than  the  tubercles,  especially  at  the  time  of  the  soften- 
ing. It  has  a  greater  tendency  than  the  tubercle  to  increase 
or  to  extend  gradually.  It  does  not  appear  to  be  susceptible 
of  being  eliminated  and  of  curing  itself  spontaneously. 

It  may  exist  in  all  the  organs:  it  is  observed  frequently  in 
the  mammae,  the  testicles,  the  uterus,  the  liver,  the  lungs,  the 
encephalon,  the  stomach,  the  periosteum,  the  dura  mater,  the 
bones,  their  medullary  membrane,  the  serous  membranes,  the 
•mucous  membrane,  the  muscles,  the  glands,  the  lymphatic 
ganglipns,  and  in  the  common  cellular  tissue. 

III.      OF  SCHIRRUS. 

§  839.  The  schirrous  or  glue-like  tissue  is   less   common 
than  the  preceding;  it  is  often  confounded  with  it  under  the 
name  of  cancer. 
*  It  exists  most  commonly  under  the  form  of  isolated  masses. 

In  the  state  of  crudity,  it  is  difficult  to  distinguish  it  from  the 
tuberculous  and  encephaloid  tissues.  It  is  hard;  but  its  con- 
sistence varies  from  that  of  cartilage,  or  of  the  rind  of  bacon, 
to  that  of  the  iritervertebral  ligaments.  It  creaks  under  the 
point  of  the. scalpel  when  scraped;  it  is  white,  bluish,  gray, 
little  coloured  or  without  colour.  It  is  semi-transparent;  it 
forms  masses  of  irregular  figures,  rarely  lobulated,  ordinarily 
homogeneous;  it  is  sometimes  divided  in  the  interior  by 
fibrous  or  cellular  intersections:  this  interior  tissue  is  some- 
times regularly  radiated,  like  that  of  a  turnip,  sometimes  alve- 
olar, sometimes  irregular.  Distinct  vessels  are  rarely  per- 
ceived in  it. 

Schirrus  assumes  the  consistence  of  jelly,  and  sometimes, 
the  appearance  of  syrup,  is  sometimes  colourless,  fulvid,  or 
greenish,  sometimes  grayish,  impure,  and  stained  with  blood. 
Sometimes  the.  softening  is  gummy,  or  pultaceous,  and  at 
others,  like  honey. 


532  GENERAL  ANATOMY. 

This  morbid  tissue  presents  a  considerable  diversity  of  ap- 
pearance, both  in  the  state  of  crudity  and  in  that  of  softening. 
Bayle  enumerates  from  five  to  six  species  of  cancers.  Several 
species  of  the  sarcoma  of  Abernethy  belong  to  this  kind  of 
tissue. 

Schirrus  softens  sometimes  partially,  and  then  it  presents 
the  appearance  of  cicatrices  (Nicod.).  In  a  case  of  this  kind, 
which  I  have  seen  recently,  it  seemed  to  me  what  appeared 
to  be  cicatrices  was  the  skin  remaining  sound  in  small  spots 
in  the  midst  of  a  very  great  number  of  superficial  and  irregu- 
lar ulcerations. 

Schirrus  has  been  observed  in  most  parts  of  the  body,  in 
almost  all  the  organs  and  tissues.  • 

IV.    OF  MELANOSIS. 

§  840.  Melanosis,*  cancer  m&lane  of  Alibert  is  a  morbid 
tissue  characterized  by  its  black  colour,  which,  noticed  at  first 
by  some  observers,  both  in  man  and  animals,  has  been  speci- 
fied and  named,  some  years  ago  by  Laennec. 

This  substance  exists  under  the  form  of  isolated  masses, 
denuded  or  enveloped,  under  that  of  infiltration,  and  of  platft 
at  the  surface  of  membranes. 

The  masses  of  melanosis  vary,  as  to  size,  from  the  most  mi* 
nute  to  that  of  a  nut:  they  exist  in  a  greater  or  less  number 
in  the  same  individual;  they  are  sometimes  tolerably  regular, 
sometimes  mamillary,  lobulated,  sometimes  as  if  formed  of 
laminae  twisted  or  winding.  These  parts  are  united  together 
and  the  masses  surrounded  by  cellular  tissue.  The  vessels 
surround  this  tissue,  but  do  not  penetrate  into  the  black  sub- 
stance. This  substance  is  black  or  brown,  opaque,  inodorous, 
tasteless,  firm,  tenacious,  and  apparently  homogeneous;  but  if 
it  be  broken  by  percussion,  and  washed  with  water,  the  water 
becomes  coloured  with  brown  or  black;  the  tissue  loses  its 
colour  and  remains  grayish. 

Melanosis  occurs  in  plates  at  the  surface  of  the  mucous  or 

*  Breschet,  Considerations  sur  une  alteration  organiijue  appeh'e  degtnt- 
rescence  noire,  etc.  Paris,  1821. 


OF   CIRRHOSIS,  &C.  533 

serous  membranes;  it  is  found  also  infiltrated  in  the  substance 
of  the  mucous  membrane,  false  membranes,  ganglions,  &c. 

Melanosis,  examined  chemically,  appears  composed,  1st,  of 
coloured  fibrine;  2d,  of  a  blackish  colouring  matter,  soluble 
in  weak  sulphuric  acid  and  in  the  solution  of  the  subcarbonate 
of  soda,  and  colouring  these  fluids  red ;  3d,  of  a  small  quantity 
of  albumen;  4th,  of  chloruret  of  sodium,  of  subcarbonate  of 
soda,  of  phosphate  of  lime  and  oxide  of  iron. 

The  composition  of  melanosis  is  then  very  analogous  to  that 
of  the  clot  of  the  blood,  that  is  to  say  to  the  colouring  matter 
and  fibrine,  both  in  a  particular  state;  three  gross  substances 
are  also  met  with  in  it. 

Melanosis  softens  slowly,  under  the  form  of  blackish  bouil- 
lie;  and,  according  to  its  seat,  this  substance  becomes  effused 
in  the  cavities,  where  it  infiltrates  in  such  a  manner  as  to  co- 
lour the  humours  and  tissues.  Sometimes,  but  rarely,  subcu- 
taneous melanosis  ulcerates;  Dr.  Ferrus  has  observed  a  case 
of  this  sort.  In  the  state  of  softening,  evei^when  extreme, 
this  tissue  has  little  tendency  to  spread  or  increase;  it  does 
not  determine  in  the  organization  a  deleterious  action  so 
marked  as  the  preceding.  The  alterations  which  have  been 
most  often  observed  are  a  general  decoloration,  dropsies,  tor- 
por, a  debility  analogous  to  what  takes  place  in  the  scurvy. 

Melanosis  has  been  found  in  many  parts,  and  especially  in 
the  common  cellular  membrane,  in  the  muscles,  in  the  heart, 
in  the  lymphatic  glands,  in  the  orbit,  in  the  eye,  in  the  lungs, 
the  liver,  the  kidneys,  the  pancreas,  the  spleen,  the  cellular 
tissue  of  the  mammas,  the  accidental  cellular  tissue,  &c. 

Melanosis  appears  to  result  from  an  aberration  of  some  of 
the  materials,  and  especially  of  the  colouring  matter  of  the 
blood. 

V.  OP  ciRRHosft  &c. 

§841.  Cirrhosis,  or  the  fulvid  morbid  tissue,  exists  some- 
times under  the  form  of  masses;  it  has  been  seen  also  under 
the  form  of  plates  and  of  a  cyst. 

fr    In  masses,  this  tissue  is  fulvid,  dull,  flaccid,  humid,  com- 
pact, analogous  to  the  tissue  of  the  renal  capsules:  it  does  not 


534  GENERAL  ANATOMY. 

present  distinct  fibres.  The  masses  vary  from  the  size  of  a 
grain  of  millet  to  that  of  a  cherry  stone.  They  exist  some- 
times in  an  innumerable  quantity.  The  largest  appear  squam- 
ous. 

This  tissue  softens  under  the  form  of  greenish  brown  pu- 
trescence; its  effects,  whether  local  or  general,  are  slightly 
marked.  It  exists  frequently  and  very  abundantly  in  the 
liver,  which  is  then  shrivelled,  wrinkled,  and  rugose.  It  has 
been  seen  also  in  the  kidney,  the  prostate,  the  epedidymis, 
the  ovarium,  and  thyroid. 

§  842.  Laennec  has  designated,  under  the  name  of  scferose, 
a  tissue  very  much  resembling  or  identical  with  the  white 
compact  tissue,  and  which  he  found  infiltrated  in  the  subperi- 
toneal  cellular  tissue  of  the  lumbar  region  in  a  cancerous  in- 
dividual. It  differs  from  the  morbid  tissues  in  that  it  has  not 
been  osberved  softened;  but  it  approximates  to  them  by  its  pro- 
pensity to  spread. 

§  843.  The  saftne  pathologist  has  designated,  under  the  name 
of  squirre  squammeux,  a  tissue  of  a  semi-transparent,  dull, 
white,  foliated  like  the  flesh  of  a  cod,  which  he  once  saw  en- 
closed in  a  pearly  cyst,  in  a  cancerous  individual. 

VI.    OF  COMPOUND  MORBID  TISSUES. 

§  844.  The  morbid  tissues  are  very  often  associated:  their 
reunion  is  one  of  the  greatest  sources  of  difficulty  in  the  study 
of  pathological  anatomy. 

The  composition  takes  place  sometimes  by  simple  juxta-po- 
sition,  and  sometimes  by  an  intimate  and  mutual  penetration. 

The  most  ordinary  combinations  are,  1st,  those  of  the  fibro- 
cartilaginous  and  osseous  tissues  in  the  cysts  which  contain 
vesicular  worms ; 

2d.  The  combination  of  earthy  ossification  and  of  the  tuber- 
cle, especially  in  the  bronchial  glands; 

3d.  That  of  the  tubercle  and  encephaloid  tissue,  frequent 
in  the  liver  and  testicles; 

4th.  That  of  schirrus  and  earthy  ossification,  common  also 
in  the  liver; 

5th.  That  of  all  the  morbid  tissues,  with  ossifications,  with 


OF  FOREIGN  ANIMATED  BODIES.  535 

other  analogous  productions,  inflammation,  hypertrophy,  se- 
rous, sanguineous,  and  purulent  infiltrations,  &c.;  which  con- 
stitutes the  compound  cancers  of  the  stomach,  of  the  mam- 
moc,  &c. 


SECTION  IV. 

OP  FOREIGN  ANIMATED  BODIES. 

§  845.  The  animals*  which  are  met  with  in  the  organiza- 
tion, and  which  live  at  its  expense,  are,  on  the  one  hand  intes- 
tinal worms,  and  on  the  other  animals  attached  to  the  surface 
of  the  body,  penetrating  into  its  substance,  introduced  into  its 
cavities,  &c.  The  knowledge  of  these  beings  is  one  of  the 
parts  of  medical  natural  history  the  most  difficult  and  most 
obscure  from  the  want  of  exact  observations. 


ARTICLE  I. 
OF  INTESTINAL  WORMS. 

§846.  Intestinal  worms  or  entozoary,t  entozoa  (Rudolphi,) 
are  formed,  or  at  least  are  born  and  inhabit  within  the  organi- 
zation; they  can  not  live  elsewhere.  They  are  found  not  only 
in  the  alimentary  canal  and  ducts  which  are  inserted  in  it, 
but  even  in  the  cellular  tissue,  in  the  muscles  and  in  the  sub- 
stance of  organs  which  are  the  most  distant  from  the  surfaces 
of  the  body,  as  the  brain.  Their  organization  presents  many 
and  great  varieties  (38).  Their  origin  is  very  obscure.  Con- 
fining ourselves  to  the  indication  of  those  which  inhabit  the 
human  body,  they  maybe  referred  to  three  orders,  viz.:  vesi- 
cular worms,  flat  worms  and  cylindrical  worms. 

*  J.  H.  loerdens,  Em 
etc.,  1801-1802. 

1810. — Idem,  Ento:  Berolini,  . 


536  GENERAL  ANATOMY. 

I.    OF  VESICULAR  WORMS. 

§847.  Vesicular  worms,*  Entozoa  cystica,  (Rud.)  con- 
sist in  great  part,  of  a  caudal  vesicle  more  or  less  voluminous, 
peculiar  to  a  single  or  common  to  several  worms:  the  body  is 
depressed  or  rounded,  always  very  small;  the  head  (wanting 
in  one  genus)  is  furnished  with  pits  (two  or  four,)  with  suckers 
(four,)  with  a  crown  of  hooks  or  of  four  recurved  probosces; 
there  is  no  visible  intestinal  canal  or  genital  organs.  These 
worms  inhabit  always  the  substance  of  the  organs  in  a  distinct 
cyst;  they  have  been  confounded  together  for  a  long  time,  and 
with  cysts,  under  the  name  of  hydatids.  Even  now  natural- 
ists reject  one  or  two  genera  from  this  order,  which  consists 
of  the  following:  JLcephalocystis,  Echinococcus,  Cysticerus, 
and  Diceras. 

§  848.  The  acephalocystis,t  a  genus  established  by  Laen- 
nec,  but  not  adopted  by  Rudolphi,  or  by  Cuvier,  consists  in 
a  vesicle,  without  head  or  body,  round  or  obround,  from  the 
size  of  a  little  pea  to  that  of  a  middling  apple,  with  thin  and 
soft,  transparent,  whitish,  homogeneous,  fragile  walls,  filled 
with  a  limpid,  aqueous,  and  albuminous  fluid.  It  is  doubtful 
whether  spontaneous  movements  have  been  observed  in  it.  It 
appears  that  these  equivocal  beings  reproduce  by  interior  buds. 
They  have  been  met  with  in  almost  all  the  organs.  Seven  or 
eight  species  are  known.  They  are  always  encysted,  if  we 
except  the  clustered  mole,  which  is  regarded  as  the  result  of 
the  reunion  or  of  the  suture  of  one  species  of  this  genus. 

§  849.  The  echinococcus,  a  genus  of  Rudolphi,  which  com- 
prehends perhaps  the  acephalocystis,and  which  Cuvier  does  not 
admit,  consists  in  a  simple  or  double  external  vesicle,  to  the 
internal  surface  of  which  are  attached  several  worms,  fine  and 
granulated  like  grains  of  sand,  whose  body  is  ovoid,  and  the 
head  (like  that  of  the  armed  tsenia)  furnished  with  a  crown  of 
hooks  and  suckers. 

*  T/aennec,  Memoire  sur  les  vers  veslculaires,  &c.,  in  the  Bulletin  de  fEcok 
de  medicine.  Paris,  an.  xiii. 

f  Laennec,  he.  tit. — Ludersen,  .Diss.  dc  hydalidibus;  (Jotting1.,  1808. — 
H.  Cloquet,  Faune  de  mcdecins,  torn.  i.  Paris,  1- 


OF  THE  FLAT  WORMS. 

One  species,  the  echinococcus  of  man,  E.  hominis,  inhabits 
the  viscera  of  man,  and  especially  the  liver. 

§  850.  The  cysticercus  has  the  body  rounded  or  depressed, 
rugose,  terminating  in  a  caudal  vesicle;  its  head  (like  that  of 
the  armed  tsenia)  is  furnished  with  four  suckers  and  with  a  re- 
curved proboscis.  It  inhabits  solitarily  a  very  thin  cyst. 

Thecysticercusofthecellulartissue,C.  ce//t//osa?,  has  the  head 
square,  the  neck  very  short  and  inflated  before,  the  body  cy- 
lindrical elongated,  the  caudal  vesicle  elliptical  transversely, 
and  is  the  species  so  common  in  the  hog;  it  is  met  with  some- 
times in  the  muscles,  the  brain,  and  the  heart  of  man.  Some 
other  species  are  also  found  in  the  human  body. 

§  851.  The  rough  diceras,  D.  rudis,  has  the  body  ovoid 
and  depressed;  it  has  a  loose  tunic;  its  head  is  provided  with 
a  bifid,  rough,  filamentous  horn.  It  is  not  exactly  known 
whether  it  inhabits  the  substance  of  organs.  It  was  discover- 
ed by  Sultzer,  in  the  matters  discharged  by  the  action  of  a 
purgative.  Considered  doubtful  by  Rudolphi,  it  has  been 
found  since  by  Le  Sauvage,  de  Caen,  who  has  sent  individuals 
to  the  Societ6  de  la  Faculte  de  Medecine,  where  I  saw  them. 

II.    OF  THE  FLAT  WORMS. 

§  852.  The  flat  worms  are  those  whose  soft  and  depressed 
bodies  is  provided  with  sucking-pores  at  its  inferior  surface 
or  at  its  extremities,  entozoa  trematoda,  (Rud.),  and  those 
whose  body  is  elongated,  continuous,  or  articulated,  and  the 
head  furnished  with  pits,  with  suckers,  with  one  or  four  pro- 
bosces,  naked  or  armed,  Ent.  cestoidea,  (Rud.)  Both  are  de- 
prived of  an  intestinal  canal,  and  provided  with  ramified  ova- 
ries. This  order  comprehends  in  the  human  body  the  genera 
Txnia,  Disfoma,  and  Polystoma. 

§  853.  The  taenia  have  the  body  very  much  elongated,  flat, 
and  articulated,  and  the  head  furnished  with  two  or  four  little 
suckers.  Two  species  are  found  in  man. 

The  broad  or  unarmed  taenia,  T.  lata,  Bothriocephalus  la- 
tus,  (Bremser,  Rud.),  has  the  head  nearly  square,  two  naked 
pit-suckers,  the  head  and  the  pits,  which  are  marginal,  oblong, 


538  GENERAL  ANATOMY. 

the  neck  almost  wanting,  the  anterior  articulations  in  the  form 
of  wrinkles,  those  which  follow  are  broad  and  short,  the  last 
elongated;  its  length  is  twenty  feet  or  more.  This  species  is 
common  in  Switzerland  and  Russia,  very  rare  in  England, 
Holland,  and  Germany.  It  is  not  found  in  dead  bodies. 

The  solitary  or  armed  tsenia,  T.  solium,  called  also  com- 
monly, and  improperly^  solitary  worm,  has  the  head  furnish- 
ed with  four  suckers,  and  an  obtuse  proboscis,*  armed  with 
hooks  in  their  centre;  the  head  is  hemispherical,  and  distinct; 
the  neck  thickens  anteriorly;  the  anterior  articulations  are 
very  short,  the  following  elongated,  the  last  longer,  all  obtuse, 
provided  each  with  a  marginal  pore,  alternating  indefinitely 
sideways;  its  length  is  from  five  to  ten  feet  and  more.  This 
species  is  common  in  England,  Holland,  and  Germany.  It 
is  sometimes  met  with  in  dead  bodies. 

Both  species  are  found  in  France,  but  particularly  the  se- 
cond. They  both  inhabit  the  intestinal  canal,  especially  the 
small  intestines. 

§  854.  The  distoma,  or  the  fasciola^  (Lin.)  has  the  body 
soft,  depressed,  and  two  solitary  pores,  one  anterior  and  one 
ventral. 

The  hepatic  distoma,  D.  hepaticum,  which  has  the  form  of 
an  oval  leaf,  is  met  with  in  the  gall  bladder  of  man  and  of 
many  other  animals,  particularly  of  the  sheep. 

The  polystoma,  hexathyridium,  (Treuther,)  has  the  body 
depressed,  six  anterior  pores,  one  ventral,  and  one  posterior. 
The  P.  of  the  fat,  P.  pinguicola,  which  is  truncated  before, 
pointed  behind,  has  been  met  with  in  a  tumour  of  the  human 
ovary.  The  polystoma  of  the  veins,  P.  venarum,  appears 
to  be  an  external  worm.  (457) 

III.    OP  CYLINDRICAL  WORMS. 

§  855.  The  cylindrical  worms,  Ent.  nematoidea,  (Rud.), 
have  the  body  elongated,  rounded,  and  elastic;  they  have  an 
intestinal  canal,  terminated  by  a  mouth  and  anus,  genital  or- 
gans, separate  on  two  different  individuals.  This  order  com- 


OF  CYLINDRICAL  WORMS.  539 

prebends,  in  man,  the  three  following  genera:  Filaria,  Tri- 
chocephahiSj  and  •flscaris. 

§  856.  The  ascaris  has  the  body  round,  tapering  at  the  two 
ends,  the  head  furnished  with  three  tubercles;  the  penis  of  the 
male  is  pointed  and  bifid.  Two  species  are  found  in  the  hu- 
man body. 

The  «#.  lumbricoideS)  the  head  of  which  is  naked,  the  body 
several  inches  long  (3  to  12),  marked  with  two  opposite  fur- 
rows, the  tail  a  little  obtuse,  inhabits  the  small  intestines.  The 
•#.  vermicular 'is ,  Oxyuris  vermicularis,  (Bremser),  has  the 
head  obtuse,  furnished  with  a  vesicular  membrane  on  each 
side;  its  body  is  a  little  thickened  anteriorly;  the  tail  of  the 
male  is  flexed  and  obtuse;  that  of  the  female  is  straight  and 
flattened.  It  inhabits  the  large  intestines,  especially  the  rec- 
tum. 

§  857.  The  trichocephalus  has  the  anterior  part  of  the  body 
capillary,  the  rest  suddenly  a  little  more  voluminous;  the 
mouth  orbicular;  the  penis  simple,  and  sheathed. 

The  T.  dispar  is  found  in  man:  it  is  unarmed;  its  capillary 
part  is  very  long,  its  head  pointed;  the  body  of  the  female  is 
nearly  straight;  that  of  the  male  is  spiral;  the  sheath  of  the 
penis  is  ovoid.  This  worm,  observed  by  Morgagni,  Wris- 
berg,  Roedorer,  and  Wagler,  is  very  common.  It  inhabits  the 
large  intestines,  and  especially  the  coecum. 

§  858.  The  filaria  has  the  body  elongated  and  nearly  equal, 
the  mouth  orbicular;  the  penis  of  the  male  is  pointed  and 
simple. 

The  F.  medinensis,  which  is  very  long,  which  has  the  head 
slender,  the  tail  flattened  and  flexed  in  the  male,  semi-cylin- 
drical, pointed,  and  curved  in  the  female,  is  met  with  in  the 
human  species,  but  only  between  the  tropics.  It  inhabits 
the  subcutaneous  cellular  tissue,  especially  that  of  the  feet. 
It  was  thought  formerly  to  be  an  exterior  penetrating  worm;  it 
appears  to  be  really  an  entozoary  one.  The  F.  of  the  bronchia?, 
F.  bronchialis,  is  a  doubtful  species,  observed  and  described 
by  Treutler,  under  the  name  of  Hamularia  lymphatica. 

§  859.  The  strongylus  gigas  has  been  numbered  among  the 
worms  which  inhabit  the  human  body,  because  Ruysch  says 


540  GENERAL  ANATOMY. 

that  he  once  saw  in  the  kidneys  of  man,  worms  similar  to 
those  of  the  kidneys  of  the  dog. 

The  spiroptera  hominis  is  a  species  yet  doubtful,  observed 
by  Messrs.  Barnett  and  Lawrence,  and  discharged  from  the 
urinary  bladder  of  a  woman. 

H.  Cloquet  has  recently  described  under  the  name  of  Ophi- 
ostoma  ponterii,  a  worm  thrown  up  by  a  man  in  vomiting, 
and  observed  by  Pontier. 

Many  other  worms  have  been  indicated  as  inhabiting  the 
human  body,  which  are  only  found  in  animals;  others  are 
only  larvae,  or  other  objects  more  or  less  analogous  to  the 
worms  which  are  found  accidentally  in  excretions,  or  which 
have  been  placed  there  by  deception. 


ARTICLE  II. 
OF    PARASITIC    ANIMALS. 

§  860.  Parasitic  animals  are  much  more  foreign  to  the  or- 
ganization than  the  entozoaric. 

Some  of  them  however  are  insects  born,  living,  and  repro- 
ducing themselves  on  the  surface  and  within  the  substance  of 
the  skin:  such  are  the  Pediculus  humanus  corporis,  P.  capi- 
tis,  P.  pubiSj  Pulex  irritans,  P.  penetrans,  and  the  Jlcarus 
scabiei  or  sarcoptes. 

Other  insects  are  deposited  under  the  skin  and  in  the  mu- 
cous cavities,  in  the  state  of  eggs,  develope  themselves  in  the 
state  of  larvae,  and  come  out  afterwards:  such  is  the  Oestrus, 
so  common  in  the  horse,  the  ox,  the  sheep,  and  which  has 
been  found  also  under  the  skin  of  man  and  in  the  sinus  of  the 
face.  Larvae  of  the  genus  Musca  and  of  some  others,  deve- 
lope themselves  also  sometimes  in  the  auricular  passage  of 
children  which  are  not  kept  clean,  at  the  surface  of  ulcers,  &c. 
We  must  not  forget  that  many  cases  of  larvae  excreted  should 
be  referred  to  deceptions  or  fortuitous  cases. 

§861.  Certain  other  animals  penetrate,  in  the  adult  state, 
into  the  mucous  cavities  of  the  body,  remain  there  a  greater 


OF  PARASITIC  ANIMALS.  541 

or  less  time,  and  cause  different  affections:  such  are,  among 
others,  leeches  Hirudo  medicinalis,  and  H.  alpina;  such  is 
probably  also  the  hair-worm,  Gordius,  It  has  been  thought 
that  the  earth-worm  could  penetrate  into  the  body,  it  is  the 
effect  either  of  a  mistake  or  of  deception.  The  Furia  Inferna- 
lis  of  Linnaeus  appears  to  be  an  imaginary  worm. 

Some  insects,  finally,  only  mechanically  wound  the  exte- 
rior surface  of  the  body,  or  deposit  a  venom  in  it;  they  are 
otherwise  entirely  foreign  to  it. 


THE  END. 


CAREY  &  LEA 

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ABDOMEN.   By  JOHJT  ABEHCROMBIE,  M.  D. 

"  We  have  now  closed  a  very  long  review  of  a  very  valuable  work,  and  al- 
though we  have  endeavoured  to  condense  into  our  pages  a  great  mass  of  impor- 
tant matter,  we  feel  that  our  author  has  not  yet  received  justice."—  Med.  Chir* 


A  COLLECTION  of  COLLOQUIAL 
PHRASES  on  every  Topic  necessary  to  maintain  Conversation, 
arranged  under  different  heads,  with  numerous  remarks  on 
the  peculiar  pronunciation  and  use  of  various  words  —  the 
whole  so  disposed  as  considerably  to  facilitate  the  acquisition 
of  a  correct  pronunciation  of  the  French.  By  A.  BOLMAR.  One 
yol.  18mo. 

XIII.  A  SELECTION  of  ONE  HUNDRED 
PERRIN'S  FABLES,  accompanied  by  a  Key,  containing-  the 
text,  a  literal  and  free  translation,  arranged  in  such  a  manner 
as  to  point  out  the  difference  between  the  French  and  the 
English  idiom,  also  a  figured  pronunciation  of  the  French,  ac- 
cording to  the  best  French  works  extant  on  the  subject;  the 


Published  by  Carey  4'  Lea.  S 

whole  preceded  by  a  short  treatise  on  the  sounds  of  the  French 
language,  compared  with  those  of  the  English. 

XIV.  The  First  Eight  Books  of  the  ADVENTURES 
of  TEJLEMACHUS,  accompanied  by  a  Key  to  facilitate  the 
translation  of  the  work. 

XV.  A  TREATISE  on.PATHOLOGICAL  ANA- 
TOMY, by  WILIIAM  E.  HORNF.R,  M.  D.  Adjunct  Professor  of 
Anatomy  in  the  University  of  Pennsylvania. 

"  We  can  conscientiously  commend  it  to  the  members  of  the  profession,  as  a 
satisfactory,  interesting,  and  instructive  >iew  of  the  subjects  discussed,  and 
as  well  adapted  to  aid  them  in  forming  a  correct  appreciation  of  the  diseased 
conditions  they  are  called  on  to  relieve."— American  Journal  of  the  Medical 
Sciences,  No.  9. 

XVI.  A  New  Edition  ofa  TREATISE  of  SPECIAL 
and  GENERAL  ANATOMY,  by  the  same  author,  2  vols.  8vo. 

XVII.  COXE'S  AMERICAN  DISPENSATORY, 

containing  the  Natural,  Chemical,  Pharmaceutical  and  Medical 
History  of  the  different  substances  employed  in  medicine,  to- 
gether with  the'  operations  of  Pharmacy  illustrated  and  ex- 
plained, according  to  the  principles  of  modern  Chemistry.  To 
which  are  added  Toxicological  and  other  tables,  the  prescrip- 
tions for  Patent  Medicines,  and  various  Miscellaneous  Prepa- 
rations. Eighth  Edition,  Improved  and  greatly  Enlarged.  By 
JOHX  REDMAN  COXE,  M.  D.  Professor  of  Materia  Medica  and 
Pharmacy  in  the  University  of  Pennsylvania.  In  1  vol.  8vo. 

XVII I.  An  ESSAY  on  REMITTENT  and  INTER- 
MITTENT DISEASES,  including  generically  MarshFever and 
Neuralgia — comprising  under  the  former,  various  anomalies, 
obscurities,  and  consequences,  and  under  a  new  systematic 
view  of  the  latter,  treating  of  tic  douloureux,  sciatica,  head- 
ache, ophthalmia,  tooth-ache,  palsy,  and  many  other  modes  and 
consequences  of  this  generic  disease;  by  JOHK  MACCUIXOCH, 
M.  D.,  F.  R.  S.  Sec.  &.c.  Physician  in  Ordinary  to  his  Royal 
Highness  Prince  Leopold,  of  Saxe  Cobourg. 

u  Dr.  Macculloch  is  a  great  philosopher  and  logician.  His  views  are  calculated 
to  do  much  good.  We  have  therefore  taken  great  pains  to  concentrate  and  dif- 
fuse them  widely  through- the  profession.  Nothing  but  a  strong  conviction  that 
the  work  before  us  contains  a  multitude  of  valuable  gems,  could  have  induced  us 
to  bestow  so  much  labour  on  the  review.  In  rendering  Dr.  Macculloch's  work 
more  accessible  to  the  profession,  we  are  conscious  that  we  are  doing  the  state 
soane  service."— Mcd.  Chir.  Review. 

w  We  most  strongly  recommend  Dr.  Macculloch's  treatise  to  the  attention  of 
our  medical  brethren,  as  presenting  a  most  valuable  mass  of  information,  on  a 
most  important  subject.''— Am.  Mcd.  and  Plum.  Journal. 

XIX.  WISTAR'S  ANATOMY,   fifth  edition,   2 

vols.  8vo. 

XX.  The  ANATOMY,  PHYSIOLOGY,  and  DIS- 
EASES of  the  TEETH.  By  THOMAS  HEM,  F.  R.  S.,  F.  L.  S. 

&c.  In  1  vol.  8vo.  with  plates. 

"Mr.  Bell  has  evidently  endeavoured  to  construct  a  work  of  reference  for  the 
practitioner,  and  a  text-book  for  the  student,  containing  a  '  plain  and  practical 
digest  of  the  information  at  present  possessed  on  the  subject,  and  results  of  the 
author's  own  investigations  and  experience.'  "  *  *  *  "  We  must  now  take  leave 
of  Mr.  Bell,  whose  work  we  have  no  doubt  will  become  a  class  book  on  the  im- 
portant subject  of  dental  sui'ge\ry."—Medico-Chirnrgical  Review, 

XXI.  MORALS   of  PLEASURE,  illustrated  bj 
Stories  designed  for  Young  Persons,  in  1  vol. 


4 


Valuable  Works 


**  The  style  of  the  stones  is  no  less  remarkable  for  its  ease  and  gracefulnew, 
than  for  the  delicacy  of  its  humour,  and  its  beautiful  and  at  times  affecting  sim- 
plicity. A  lady  must  have  written  it  —  for  it  is  from  the  bosom  of  v.  onuni  alone, 
that  such  tenderness  of  feeling  and  such  delicacy  of  sentiment—  such  S-.N  eet  les- 
sons of  morality—  such  deep  and  pure  streams  of  virtue  and  piety,  gush  forth  to 
cleanse  the  .juvenile  mind  from  the  grosser  impurities  of  our  nature,  and  prepare 
the  young  for  lives  of  usefulness  here,  and  happiness  hereafter.  \Ve  advise  pa- 
rents of  young  families  to  procure  this  little  book—  assuring  them  that  it  will 
have  a  tendency  to  render  their  offspring  as  sweet  as  innocent,  as  innocent  us 
It  is  dedicatad  by  the  author  '  to  her  young  Bedford 


cay,  as  gay  as  happy. 
friends,  Anna  ana  Ma 


We  would  advise  so 


aria  Jay'  —  but  who  this  fair  author  is,  we  cannot  ev 
me  sensible  educated  baekelor  to  find  out."—  -JV.  T.  C 


oin.  Adv. 


XXII.   The  PRACTICE  of  PHYSIC,  by  W.  P. 

DEWEES,  M.  D.  Adjunct  Professor  of  Midwifery  in  the  University 
of  Pennsylvania,  2  vols.  8vo. 


The  profession  need  not  be  informed  how  much  a  work  like  that  now  pub- 
lished was  wanted.  It  has  been  the  particular  object  of  the  author  to  endeavour 
to  accommodate  the  mode  of  managing  the  diseases  of  •which  he  trciis  to  the 
many  pathological  discoveries  recently  made,  both  in  this  country  and  i  it  Europe; 
and  having  also  availed  himself  of  Jhis  long  experience,  he  trusts  that  his  work 
•will  remove  many  of  the  embarrassments  experienced  by  practitioners. 

XXIII.  DEWEES  on  the  DISEASES  of  CHIL- 
DREN. Third  edition.  In  8vo. 

The  objects  of  this  work  are,  1st,  to  teach  those  who  have  the  charge  of  chil- 
dren, either  as  parent  or  guardian,  the  most  approved  methods  of  securing  and 
improving  their  physical  powers.  This  is  attempted  by  pointing  out  the  du- 
ties which  the  parent  or  the  guardian  owes  for  this  purpose,  to  this  interesting, 
but  helpless  class  of  beings,  and  the  manner  by  which  their  duties  shall  be  ful- 
filled. And  2d,  to  render  available  a  long  experience  to  these  objects  of  our  af- 
fections, when  they  become  diseased.  In  attempting  this,  the  author  has  avoided 
as  much  as  was  possible,  "technicality;"  and  has  given,  if  he  does  not  flatter  him- 
self too  much,  to  each  disease  of  which  he:  treats,  its  appropriate  and  designat- 
ing characters,  A\ith  a  fidelity  that  will  prevent  any  two  being  confounded,  to- 
gether with  the  best  mode  of  treating  them,  that  either  his  own  experience  or 
that  of  others  has  suggested. 

XXIV.  DEWEES  on  the  DISEASES  of  FEMALES. 

Second  edition  with  additions.     In  Svo. 

XXV.  DEWEES'S  SYSTEM  of  MIDWIFERY. 

Fourth  edition,  with  additions. 

XXVI.  CHAPMAN'S  THERA.PEUTICSandMA- 

TERIA  MEDICA.     Fifth  edition,  with  additions. 

XXVII.  The  ATLANTIC  SOUVENIR,  for  1 830,  in 
elegant  fancy  leather  binding1,  and  with  numerous  embellish- 
ments by"  the  best  Artists. 

The  publishers  have  spared  neither  pains  nor  expepse  in  endeavouring  to 
render  this,  their  fifth  annual  volume,  still  more  worthy  the  high  degree  of  fa- 
vour which  its  predecessors  have  enjoyed.  A II  the  impressions  being  from  steel 
render  them  equally  perfect,  and  the  binding  being  a  fancy  leather,  the  \\holu 
•will  be  rendered  more  permanent.  In  the  list  of  Authors  will  be  found  many 
of  the  most  distinguished  writers  in  this  country. 

A  few  copies  remain  unsold  of  the  ATLANTIC  SOUVENIR, 
a  Christmas  and  New  Year's  Present  for  1827,  1828,  and  1829, 
with  numerous  embellishments  by  the  best  Artists. 

XXVIII.  A  CHRONICLE  of  the  CONQUEST  of 
GRENADA,  by  WASHINGTON  IRVING,  Esq.  in  2  vols. 

«  On  the  whole,  this  work  will  sustain  the  high  fame  of  Washington  Irving. 
It  fills  a  blank  in  the  historical  library  which  ought  not  to  have  remained  so 
long  a  blank.  The  language  throughout  is  at  once  chaste  and  animated;  and 
the  narrative  may  be  said,  like  Spencers  Fairy  Queen,  to  present  one  long  gal- 
lery of  splendid  pictures.  Indeed,  we  know  no  pages  from  which  the  artist  is 
more  likely  to  derive  inspiration,  nor  perhaps  are  there  many  incidents  in  litei 
rary  history  more  surprising  than  that  this  antique  and  chivalrous  story  should 
have  been  for  the  first  time  told  worthily  by  the  pen  of  an  American  and  a  WH 
publicau."—L<mdott  Literary  Gazette* 


Published  by  Carey  fy  Lea.  5 

• 
Recently  published  new  Editions  of  the  following  works 

by  the  same  Author. 
THE  SKETCH  BOOK,  2  vols.  12mo. 

KNICKERBOCKER'S  HISTORY  of  NEW  YORK,  2  vols. 
12mo. 

BRACEBRIDGE  HALL,  2  vols.  12mo. 
TALES  of  a  TRAVELLER,  2  vols.  12mo. 

XXIX.  NEUMAN'S  SPANISH  and  ENGLISH 

DICTIONARY,  new  Edition. 

XXX.  The  WISH-TON-WISH,  by  the  Author  of 
the  SPY,  PIONEERS,  RED  ROVER,  &c.  in  2  vols.  12mo. 

"  We  can  conceive  few  periods  better  calculated  to  offer  a  promising  field  to 
the  novelist  than  that  which  these  pages  illustrate; — the  mingling  of  w  ildest  ad- 
venture with  the  most  plodding  industry — the  severe  spirit  of  the  religion  of  the 
first  American  settlers — the  feelings  of  household  and  home  at  variance  with  all 
earlier  associations  of  country — the  magnificence  of  the  sceneiy  by  which  they 
were  surrounded — their  neighbourhood  to  that  most  picturesque  and  extraordi- 
nary of  people  we  call  savages; — these,  surely,  are  materials  for  the  novelist,  and 
in  Mr.  Cooper's  hands  they  have  lost  none  of  their  interest.  We  shall  not  attempt 
to  detail  the  narrative,  but  only  say  it  is  well  worthy  of  the  high  reputation  of 
its  author.  All' the  more  serious  scenes  are  worked  up  to  theTiighest  pitch  of 
excitement;  if  any  where  we  have  to  complain  of  aught  like  failure,  it  is  in  the 
lighter  parts,  and  some  of  the  minor  details,  which  are  occasionally  spun  out 
too  much."— London  Literary  Gazette. 

New  Editions  of  the  following  Works  by  the  same 

Author. 

The  RED  ROVER,  in  2  vols.  12mo. 
The  SPY,  2  vols.  12mo. 
The  PIONEERS,  2  vols.  12mo. 
The  PILOT,  a  Tale  of  the  Sea,  2  vols.  12mo. 
LIONEL  LINCOLN,  or  the  LEAGUER  of  BOSTON,  2  vols. 
The  LAST  of  the  MOHICANS,  2  vols.  12mo. 
The  PRAIRIE,  2  vols.  12mo. 

XXXI.  A  TOUR  in  AMERICA,  by  BASIL  HALL, 
Captain,  R.  N.  in  2  vols.  12mo. 

XXXII.  AMERICAN  ORNITHOLOGY,  or  NA- 
TURAL   HISTORY  of  BIRDS    inhabiting    the    UNITED 
STATES,   by  CHARLES  LUCIAJT  BONAPARTE;  designed  as  a 
continuation  of  Wilson's  Ornithology,  vols.  I.,  H.  and  III. 

*»*  Gentlemen  who  possess  Wilson,  and  are  desirous  of  ren- 
dering1 the  work  complete,  are  informed  that  the  edition  of 
this  work  is  very  small,  and  that  but  a  very  limited  number  of 
copies  remain  unsold. 

XXXI II.  The  AMERICAN  QUARTERLY  RE- 
VIEW, No.  XV.    Contents.— The  Gulistan  of  Sadi.— -Napoleon 
and  Bourienne. — Anthon's  Horace. — Falkland  and  Paul  Clif- 
ford.— Tanner's  Indian    Narrative. — Dramatic    Literature.— 
British  Debate  concerning  Mexico. — Sunday  ;Mails. — Life  of 
Sir  Thomas  Munro. — Fanatical  Guides. — Terms,  Jive  dollars 
per  annum. 

XXXIV.  The  AMERICAN  JOURNAL  of  the  ME- 
DICAL SCIENCES,  No.  XII.  for  August,  1830.     Among  the 
Collaborators  of  this  work  are  Professors  Bigelow,  Channing, 
Chapman,  Coxe,  Davidge,  De  Butts,  Dewees,  Dickson,  Dud- 


Valuable  Works 


ley,  Francis,  Gibson,  Godman,  Hare,  Henderson,  Horner, 
Hosack,  Jackson,  Macneven,  Mott,  Mussey,  Physick,  Potter, 
Sewall,  Warren,  and  Worthington;  Drs."  Daniell,  Emerson, 
Fearn,  Griffith,  Hays,  Hayward,  Ives,  Jackso-n,  King,  Moultrie, 
Spence,  Ware,  and  Wright.  —  Terms,  five  dollars  per  annum. 

XXXV.  EVANS'S   MILLWRIGHT  and  MIL- 
LER'S GUIDE.  New  edit,  with  additions,  by  Dr.  T.  P.  JOKES 

XXXVI.  HUTIN'S    MANUAL    of    PHYSIO- 
LOGY, in  12mo. 

XXXVII.  HISTORICAL,    GEOGRAPHICAL, 
and  STATISTICAL  AMERICAN  ATLAS,  folio. 

XXXVIII.  MANUAL  of  MATERIA  MEDICA 

and  PHARMACY.  By  H.M.ED  WARDS,  M.D.  andP.VAVASSErn, 
M.  D.  comprising  a  Concise  Description  of  the  Articles  used 
in  Medicine;  their  Physical  and  Chemical  Properties;  the  Bo- 
tanical Characters  of  the  Medicinal  Plants;  the  Formulae  for  the 
Principal  Officinal  Preparations  of  the  American,  Parisian, 
Dublin,  Edinburgh,  &c.  Pharmacopoeias;  with  Observations  on 
the  Proper  Mode  of  Combining  and  Administering  Remedies. 
Translated  from  the  French,  with  numerous  Additions  and 
Corrections,  and  adapted  to  the  Practice  of  Medicine  and  to 
the  Art  of  Pharmacy  in  the  United  States.  By  JOSEPH  TOGXO, 
M.  D.  Member  of  the  Philadelphia  Medical  Society,  and  E. 
DtrRAin>,  Member  of  the  Philadelphia  College  of  Pharmacy. 

"  It  contains  all  the  pharmaceutical  information  that  the  physician  can  desire, 
and  in  addition,  a  largt-r  mass  of  information,  in  relation  to  the  properties,  &c. 
of  the  different  articles  and  preparations  employed  in  medicine,  than  any  of  tlve 
dispensatories,  and  we  think  will  entirely  supersede  all  these  publications  in  the 
library  of  the  physician."—  Am.  Journ.  of  the  Medical  Sciences. 

XXXIX.  An  EPITOME  of  the  PHYSIOLOGY, 
GENERAL  ANATOMY,  and  PATHOLOGY  of  BICHAT,  by 
THOMAS  HENDERSON,  M.  D.  Professor  of  the  Theory  and  Prac- 
tice of  Medicine  in  Columbia  College,  Washington  City.     1 
vol.  8vo. 

"  The  epitome  of  Dr.  Henderson  ought  and  must  find  a  place  in  the  library 
of  every  physician  desirous  of  useful  knowledge  for  himself,  or  of  being  instru- 
mental in  imparting  it  to  others,  whose  studies  he  is  expected  to  superintend."— 
North  American  Medical  and  Surgical  Journal,  No.  15. 

XL.  ADDRESSES  DELIVERED  on  VARIOUS 

PUBLIC  OCCASIONS,  by  JOHN  D.  GODMAN,  M.  D.  late 
Professor  of  Natural  History  to  the  Franklin  Institute,  Profes- 
sor of  Anatomy,  &c.  in  Rutgers  College,  &c.  &c.  With  an 
Appendix,  containing  a  Brief  Explanation  of  the  Injurious 
Effects  of  Tight  Lacing  upon  the  Organs  and  Functions  of 
Respiration,  Circulation,  Digestion,  &c.  1  vol.  8vo. 

XLI.  ELLIS'  MEDICAL  FORMULARY.    The 

Medical  Formulary,  being  a  collection  of  prescriptions  de- 
rived from  the  writings  and  practice  of  many  of  the  most  emi- 
nent physicians  in  America  and  Europe.  To  which  is  added 
an  Appendix,  containing  the  usual  dietetic  preparations  and 
antidotes  for  poisons.  The  whole  accompanied  with  a  few 
brief  pharmaceutic  and  medical  observations.  By  BENJAMIN 
ELLIS,  M.  D.  Professor  of  Materia  Medica  and  Pharmacy  in  the 
Philadelphia  College  of  Pharmacy.  2d  edition,  with  additions. 


Published  by  Carey  fy  Lea.  7 

•  Cf  A  small  and  very  useful  volume  has  been  recently  published  in  this  city,  en- 
titled '  The  Medical  Formulary.'  We  believe  that  this  volume  \\ill  meet  with  a 
cordial  welcome  from  the  medical  public.  We  would  especially  recommend  it 
to  our  brethren  in  distant  parts  of  the  country,  whose  insulated  situations  may 
prevent  them  from  having  access  to  tin.-  many" authorities  which  have  been  con- 
sulted in  arranging  materials  for  this  work."— Phil.  Merl.  and  Phys.  Jour. 

XLll.  ELEMENTS  of  PHYSICS,  or  NATU- 
RAL PHILOSOPHY,  GENERAL  and  MEDICAL,  explained 
independently  of  TECHNICAL  MATHEMATICS,  and  con- 
taining- New  Disquisitions  and  Practical  Suggestions.  By 
NEIL  AHNOTT,  M.  D.  First  American  from  the  third  London 
edition,  with  additions,  by  ISAAC  HAYS,  M.  D. 

***  Of  this  work  four  editions"  have  been  printed  in  England  in  a  very  short 
time.  All  the  Reviews  speak  of  it  in  the  hightest  terms. 

XLI1I.  LA  FAYETTEin  AMERICA,  in  1824 and 

1825;  or  a  Journal  of  a  Voyage  to  the  United  States,  by 
A.  LEVASSEUR,  Secretary  to  the  General  during1  his  journey, 
2  vols,  12mo.  Translated  by  Joasr  D.  GODMAX,  M.  D. 

XL1V.  Major  LONG'S  EXPEDITION  to  the 
ROCKY  MOUNTAINS,  2  vols.  8vo.  with  4to  Atlas. 

XLV.  Major  LONG'S  EXPEDITION  to  the 
SOURCES  of  the  MISSISSIPPI,  2  vols.  8vo.  with  Plates. 

XLVI.  NOTIONS  of  the  AMERICANS,  by  a  Tra- 
velling Bachelor,  2  vols.  12mo.  By  the  Author  of  the  SPY, 
PIONEERS,  &c. 

XLVII.  The  HISTORY  of  LOUISIANA,  particu- 
larly of  the  Cession  of  that  Colony  to  the  United  States  of 
North  America?  with  an  introductory  Essay  on  the  Constitu- 
tion and  Government  of  the  United  States,  byM.  DE  MARBOIS, 
Peer  of  France,  translated  from  the  French  by  an  American 
citizen,  in  1  vol.  8vo. 

"  From  the  extracts  with  which  we  have  indulged  our  readers,  they  will  be 
able  to  form  an  idea  of  the  character  and  spirit  of'M.  de  Marbois's  performance. 
The  outline  which  we  have  drawn,  however,  does  very  scanty  justice  to  the  me- 
rits of  the  whole  work,  which,  we  repeat,  is  in  our  judgment  the  best  that  has  re- 
cently appeared,  either  at  home  or  abroad,  on  some  of  the  most  important  topics 
Of  American  history  and  politics.  If  we  do  not  agree  with  all  the  author's  opi- 
nions, we  cannot  but  accord  to  him  unqualified  praise  for  his  fairness,  liberality, 
good  judgment,  and  enlightened  views.  The  volume  will  be  a  treasure  among 
the  historical  annals  of  the  country.  We  are  glad  to  know  that  a  translation  of 
it  by  a  competent  hand  is  in  progress  in  Paris,  and  will  speedily  be  published  in 
the  United  States."— Nori h  American  Review. 


IN  THE  PRESS, 
I.  The  YOUNG  LADIES'  BOOK,  a  Manual  of 

Instructive  Exercises,  Recreations  and  Pursuits.    'With  nu- 
merous plates. 

This  is  a  work  recently  published  by  Messrs.  Vizetelly,  Branston  &  Co.  Lon- 
don, with  upwards  of  seven  hundred  embellishments,  engraved  in  a  superior 
style  on  wood.  The  volume  is  a  duodecimo  of  more  than  five  hundred  pages, 
and  sells  in  England  for  one  guinea.  It  is  intended  to  make  the  American  edi- 
tion a  perfect  fac-simile,  or  as  nearly  so  as  practicable  in  this  country,  and  to  a£- 
ford  it  at  £  4,  neatly  bound  in  silk,  and  elegantly  gilt.  This  work  cannot  be 
classed  as  Annual,  but  may  be  said  to  be  a  Perennial,  a  suitable  memorial  for  all 
times  and  seasons.  It  differs  essentially  from  the  whole  class  of  Literary  Gifts 
usually  presented  to  Young  Ladies,  being  a  complete  manual  for  all  those  ele- 
gant pursuits  which  grace  the  person  and  adorn  the  mind.  The  London  pub- 
lishers state  that  the  various  subjects  of  which  the  volume  is  composed,  have 
been  confined  to  proficients  in  their  several  departments,  and  the  engravings 
have  been  executed  in  the  best  style  of  the  English  artists. 


8  Valuable  Works,  fyc. 

II.  CHEMISTRY  APPLIED  to  the  ARTS,  on 

the  basis  of  Gray's  Operative  Chemist.  In  8vo.  with  nu- 
merous plates. 

III.  The    PRINCIPLES   and    PRACTICE    of 

MEDICINE,  by  SAMUEL  JACKSQX,  M.  D. 

IV.  EXAMINATION    of     MEDICAL      DOC- 
TRINES and  SYSTEMS  of  NOSOLOGY,  preceded  by  PRO- 
POSITIONS  containing  the  SUBSTANCE  of  PHYSIOLOGI- 
CAL  MEDICINE,   by  F.  J.  V.  BUOUSSAIS,    Officer   of  the 
Royal  order  of  the  Leg-ion  of  Honour;  Chief  Physician  and 
First  Professor  in  the  Military  Hospital  for  Instruction  at  Pa- 
ris, &.c.  &c.  &c.    Third  edition.     Translated  from  the  French, 
by  ISAAC  HAYS,  M.  D.  and  R.  E.  GRIFFITH,  M.  D. 

V.  BECLARD'S  GENERAL  ANATOMY,  in  1 

vol.  8vo. 

VI.  FARRADAY'S  CHEMICAL  MANIPULA- 
TION, first  American,  from  the  second  London  edition. 

VII.  THOMPSON  on  INFLAMMATION,  second 

American,  from  the  second  London  edition. 

VIII.  WILLIAMS  on  DISEASE  of  the  LUNGS. 

IX.  ARNOTT'S  ELEMENTS  of  PHYSICS,  or 
NATURAL  PHILOSOPHY,  GENERAL  and  MEDICAL,  ex- 
plained independently  of  TECHNICAL  MATHEMATICS— 
Second  volume. 

X.  A  TREATISE  ON  FEVER.    By  SOUTHWOOD 
SMITH,  M.  p.  Physician  to  the  London  Fever  Hospital. 

"  For  simplicity  of  arrangement,  perspicuity  of  view,  power  of  argument 
and  practical  deduction,  this  Treatise  on  Fever  stands  without  competition,  at 
the  head  of  all  that  has  been  written  on  this  abstruse  disease."—  Westminster 
Review,  Jan. 

"Therein  no  man  in  actual  practice  in  this  metropolis,  who  should  not  pos- 
sess himself  of  Dr.  Smith's  work." — London  Medical  and  Surgical  Journal,  Feb. 

"  While  the  study  of  this  work  must  be  a  matter  of  duty  to  the  members  of  the 
medical  profession,  the  general  reader  will  find  it  perfectly  intelligible,  and  of 
great  practical  utility."—  Monthly  Repository,  March. 

u  With  a  mind  so  framed  to  accurate  observation,  and  logical  deduction,  Dr. 
Smith's  delineations  are  peculiarly  valuable."— Medico-Chir,  Jtev.  March. 

XI.  The  MUSSULMAN,  by  R.  R.  MADDEN,  Esq. 
author  of  Travels  in  Turkey,  Egypt,  Nubia,  and  Palestine,  in. 
2  vols. 

•  **  The  portraiture  of  Turkish  life  and  character,  which  this  work  exhibits,  has 
perhaps, never  been  equalled.  The  account  of  Mohamed  Ali,  the  destruction 
of  ithe  Mamelukes,  the  picture  of  Bedouin  warfare,  the  description  of  the  Der- 
vish, and  of  the  Arabian  Astrologer,  are  indeed  among-the  most  splendid  deli- 
neations ever  introduced  into  the  pages  of  fiction."— Sun. 

.  XII.  The  ARMENIANS,  a  Tale  of  Constantino- 
ple, by  J.  MACFAtttAND,  in  2  vols. 

"  The  author  will  appreciate  our  respect  for  his  talents,  when  we  say  that  he 
has  done  more  than  any  other  man  to  complete  the  picture  of  the  East,  dashed 
off  by  the  bold  pencil  of  the  author  of  Anastasius."— Edin.  Lit.  Journ. 

XIII.  JOURNAL  of  the  HEART,  edited  by  the 
Authoress  of  FLIRT ATIOX. 

"  This  is  a  most  charming  and  feminine  volume,  one  delightful  for  a  woman 
to  read,  and  for  a  woman  to  have  written;  elegant  language,  kind  and  gentle 
thoughts,  a  sweet  and  serious  tone  of  religious  feeling  run  through  every  page, 
and  any  extract  must  do  very  scanty  justice  to  the  merit  of  the  whole.  **»»«* 
We  most  cordially  recommend  this  Journal  of  the  Heart,  though  we  are  unable 
to  do  it  justice  by  any  selection  of  its  beauties,  which  are  too  ultimately  inter- 
woven to  admit  of  separation."— Literary  Gazette. 


Philadelphia,  May,  1830. 
Just  Published,  by  Carey  <$f  Lea, 

And  sold  in  Philadelphia  by  E.  L.  Carey  $  A.  Hart;  in  New-York 
by  G.  $•  C.  &  H.  Carvill ;  in  Boston  by  Carter  &•  Hendee — in  Charleston 
by  W.  H.  JBerreU—in  New-Orleans  by  W.  M'Kean;  by  the  principal 
booksellers  throughout  the  Union, 

AND  IN  LONDON,  BY  JOHN  MILLER,  ST.  JAMES'S  STREET. 

VOLUMES  III. 

CONTAINING  ABOUT    150O  ARTICLES, 

( To  le  continued  at  intervals  of  three  months,) 

OF  THE 

ENCYCLOPAEDIA  AMERICANA: 

A 

POPULAR  DICTIONARY 

OF 

ARTS,  SCIENCES,  LITERATURE,  HISTORY,  AND  POLITICS, 

BROUGHT  DOWN  TO   THE  PRESENT   TIME  AND  INCLUDING  A  COPIOUS 
COLLECTION  OF  ORIGINAL  ARTICLES  IN 

AMERICAN  BIOGRAPHY: 

On  the  basis  of  the  Seventh  Edition  of  the  German 

CONVERSATIONS-LEXICON. 


EDITED  BY  DR.  FRANCIS  LIEBER, 
ASSISTED  BY  EDWARD  WIGGLESWORTH,  ESQ. 


To  be  completed  in  twelve  large  volumes,  octavo,  price  to  subscribers,  boitnd 
in  cloth,  two  dollars  and  a  half  each. 

EACH  VOLUME  WILL  CONTAIN  BETWEEN  600  AND  700  PAGES. 


THE  CONVERSATION  LEXICON,  of  which  the  seventh  edition  in 
twelve  volumes  has  lately  heen  published  in  Germany,  origin- 
ated about  fifteen  years  since.  It  was  intended  to  supply  a  want 
occasioned  by  the  character  of  the  age,  in  which  the  sciences, 
arts,  trades,  and  the  various  forms  of  knowledge  and  of  active 
life,  had  become  so  much  extended  and  diversified,  that  no  in- 
dividual engaged  in  business  could  become  well  acquainted 
with  all  subjects  of  general  interest ;  while  the  wide  diffusion 
of  information  rendered  such  knowledge  essential  to  the  charac- 
ter of  an  accomplished  man.  This  want,  no  existing  works 
were  adequate  to  supply.  Books  treating  of  particular  branch- 
es, such  as  gazetteers,  &c.  were  too  confined  in  character; 
while  voluminous  Encyclopaedias  were  too  learned,  scientific! 


2  ENCYCLOPAEDIA    AMERICANA. 

and  cumbrous,  being  usually  elaborate  treatises,  requiring1  much 
study  or  previous  acquaintance  with  the  subject  discussed.  The 
conductors  of  the  CONVERSATION  LEXICON  endeavored  to  select 
from  every  branch  of  knowledge  what  was  necessary  to  a  well- 
informed  mind,  and  to  give  popular  views  of  the  more  abstruse 
branches  of  learning  and  science ;  that  their  readers  might  not 
be  incommoded,  and  deprived  of  pleasure  or  improvement,  by 
ignorance  of  facts  or  expressions  used  in  books  or  conversation. 
Such  a  work  must  obviously  be  of  great  utility  to  every  class  of 
readers.  It  has  been  found  so  much  so  in  Germany,  that  it 
is  met  with  everywhere,  among  the  learned,  the  lawyers,  the 
military,  artists,  merchants,  mechanics,  and  men  of  all  stations. 
The  reader  may  judge  how  well  it  is  adapted  to  its  object, 
from  the  circumstance,  that  though  it  now  consists  of  twelve 
volumes,  seven  editions,  comprising  about  ONE  HUNDRED  THOU- 
SAND COPIES,  have  been  printed  in  less  than  fifteen  years.  It 
has  been  translated  into  the  Swedish,  Danish  and  Dutch  lan- 
guages, and  a  French  translation  Is  now  preparing  in  Paris. 

A  great  advantage  of  this  work  is  its  liberal  and  impartial 
character ;  and  there  can  be  no  doubt  that  a  book  like  the  EN- 
CYCLOPEDIA AMERICANA  will  be  found  peculiarly  useful  in  this 
country,  where  the  wide  diffusion  of  the  blessings  of  education, 
and  the  constant  intercourse  of  all  classes,  create  a  great  de- 
mand for  general  information. 

In  the  preparation  of  the  work  thus  far,  the  Editors  have 
been  aided  by  many  gentlemen  of  distinguished  ability ;  and  for 
the  continuation,  no  efforts  shall  be  spared  to  secure  the  aid  of 
all  who  can,  in  any  way,  contribute  to  render  it  worthy  of 
patronage. 

The  American  Biography,  which  is  very  extensive,  will  be 
furnished  by  MR.  WALSH,  who  has  long  paid  particular  atten- 
tion to  that  branch  of  our  literature,  and  from  materials  in  the 
collection  of  which  he  has  been  engaged  for  some  years.  For 
obvious  reasons,  the  notices  of  distinguished  Americans  will  be 
confined  to  deceased  individuals:  the  European  biography  con- 
tains notices  of  all  distinguished  living  characters,  as  well  as 
those  of  past  times. 

The  articles  on  Zoology  have  been  written  expressly  forthe 
present  edition  by  DR.  JOHN  D.  GODMAN  ;  those  on  Chemistry 
and  Mineralogy,  by  a  gentleman  deeply  versed  in  those  de- 
partments of  science. 

In  relation  to  the  Fine  Arts,  the  work  will  be  exceedingly 
rich.  Great  attention  was  given  to  this  in  the  German  work, 
and  the  Editors  have  been  anxious  to  render  it,  by  the  necessary 
additions,  as  perfect  as  possible. 

To  gentlemen  of  the  Bar,  the  work  will  be  peculiarly  valua- 
ble, as  in  cases  where  legal  subjects  are  treated,  an  account  is 


ENCYCLOPEDIA    AMERICANA.  3 

given  of  the  provisions  of  American,  English,  French,  Prussian, 
Austrian,  and  Civil  Law. 

The  Publishers  believe  it  will  be  admitted,  that  this  work  is 
one  of  the  cheapest  ever  published  in  this  country.  They  have 
been  desirous  to  render  it  worthy  of  a  place  in  the  best  libraries, 
while  at  the  same  time  they  have  fixed  the  price  so  low  as  to 
put  it  within  the  reach  of  all  who  read. 

Those  who  can.  by  any  honest  modes  of  economy,  reserve  the  sum  of  two 
dollars  and  fifty  cents  quarterly,  from  their  family  expenses,  may  pay  for  tlris 
work  as  fast  as  it  is  published ;  and  we  confidently  believe  that  they  will  find 
at  the  end  that  they  never  purchased  so  much  general,  practical,  useful  infor- 
mation at  so  cheap  a  rate. — Journal  of  Education. 

If  the  encouragement  to  the  publishers  should  correspond  with  the  testimony 
in  favor  of  their  enterprise,  and  the  beautiful  and  faithful  style  of  its  execu- 
tion, the  hazard  of  the  undertaking,  bold  as  it  was,  will  be  well  compensated; 
and  our  libraries  will  be  enriched  by  the  most  generally  useful  encyclopedic 
dictionary  that  has  been  offered  to  the  readers  of  the  English  language.  Full 
enough  for  the  general  scholar,  and  plain  enough  for  every  capacity,  it  is  far 
more  convenient,  in  every  view  and  form,  than  its  more  expensive  and  ponder 
ous  predecessors — American  Farmer. 

The  high  reputation  of  the  contributors  to  this  work,  will  not  fail  to  insure 
it  a  favorable  reception,  and  its  own  merits  will  do  the  rest. — Silliman's  Joum. 

The  work  will  be  a  valuable  possession  to  every  family  or  individual  that 
can  afford  to  purchase  it ;  and  we  take  pleasure,  therefore,  in  extending  ths 
knowledge  of  its  merits. — National  Intelligencer. 

The  Encyclopaedia  Americana  is  a  prodigious  improvement  upon  all  that 
has  gone  before  it;  a  thing  for  our  country,  as  well  as  the  country  that  gave 
it  birth,  to  be  proud  of;  an  inexhaustible  treasury  of  useful,  pleasant  and  fa- 
miliar learning  on  every  possible  subject,  so  arranged  as  to  be  speedily  and 
safely  referred  to  on  emergency,  as  mell  as  on  deliberate  inquiry ;  and  better 
still,  adapted  to  the  understanding^^  put  within  the  reach  of  the  multitude. 
*  *  *  The  Encyclopaedia  ArneHNina  is  a  work  without  which  no  library 
worthy  of  the  name  can  hereafter  be  made  up. — Yankee. 

The  copious  information  which,  if  a  just  idea  of  the  whole  may  be  formed 
from  the  first  volume,  this  work  affords  on  American  subjects,  fully  justifies 
its  title  of  an  American  Dictionary;  while  at  the  same  time  the  extent,  varie- 
ty, and  felicitous  disposition  of  its  topics,  make  it  the  most  convenient  and 
satisfactory  Encyclopaedia  that  we  have  ever  seen. — National  Journal. 

If  the  succeeding  volumes  shall  equal  in  merit  the  one  before  us,  we  may 
confidently  anticipate  for  the  work  a  reputation  and  usefulness  which  ought 
to  secure  for  it  the  most  flattering  encouragement  and  patronage.— -Federal 
Gazette. 

The  variety  of  topics  is  of  course  vast,  and  they  are  treated  in  a  manner 
which  is  at  once  so  full  of  information  and  so  interesting,  that  the  work,  in 
stead  of  being  merely  referred  to,  might  be  regularly  perused  with  as  much 
pleasure  as  profit. — Baltimore  American. 

We  view  it  as  a  publication  worthy  of  the  age  and  of  the  country,  and  can- 
not but  believe  the  discrimination  of  our  countrymen  will  sustain  the  publish- 
ers, and  well  reward  them  for  this  contribution  to  American  Literature.— 
Baltimore  Patriot. 

We  cannot  doubt  that  the  succeeding  volumes  will  equal  the  first,  and  we 
hence  warmly  recommend  the  work  to  the  patronage  of  the  public,  as  being  by 
far  the  best  work  of  the  kind  ever  offered  for  sale  in  this  country. —  U.  S.  Oat. 

It  reflects  the  greatest  credit  on  those  who  have  been  concerned  in  its  pro- 
duction, and  promises,  in  a  variety  of  respects,  to  be  the  best  as  well  as  the 
most  compendious  dictionary  of  the  arts,  sciences,  history,  politics,  biography, 
&c.  which  has  yet  been  compiled.  The  style  of  the  portion  we  have  read 
is  terse  and  perspicuous ;  and  it  is  really  curious  how  so  much  scientific  and 
other  information  could  have  been  so  satisfactorily  communicated  in  such  brief 
limits.— JV.  Y.  Evening  Post. 

A  compendious  library,  and  invaluable  book  of  reference.— JV.  Y.  JSmeritm 


4  ENCYCLOPAEDIA    AMERICANA* 

This  cannot  but  prove  a  valuable  addition  to  the  literature  of  the  age.— Msr 
Advertiser. 

The  appearance  of  the  first  volume  of  this  valuable  work  in  this  country,  i« 
an  event  not  less  creditable  to  its  enterprising  publishers,  than  it  is  likely  to 
prove  lastingly  beneficial  to  the  public.  When  completed,  according  to  the 
model  presented  by  the  first  volume,  it  will  deserve  to  be  regarded  as  the  spirit 
of  all  the  best  Encyclopaedias,  since  it  comprises  whatever  is  really  desirable 
and  necessary  in  them,  and  in  addition,  a  large  proportion  of  articles  entirely 
original,  or  expressly  written  for  its  page's.  This  is  the  condition  of  all  the 
articles  of  American  Biography,  by  Mr.  Walsh ;  those  on  Zoology,  hy  Dr.  God- 
rnaii ;  and  those  on  Mineralogy  and  Chemistry,  by  a  gentleman  of  Boston, 
distinguished  for  his  successful  devotion  to  those  studies.  The  work  abounds 
with  interesting  and  useful  matter,  presented  in  a  condensed  and  perspicuous 
style;  nor  is  it  one  of  its  least  commendations  that  it  is  to  be  comprised  in 
twelve  octavo  volumes,  which  ma>  be  placed  on  an  office  table,  or  occupy  a 
shelf  in  the  parlor,  ever  ready  for  immediate  reference,  instead  of  requiring 
almost  a  room  to  itself,  like  its  ponderous  predecessors,  the  Britannica,  Edinr 
burgensis,  &c. 

The  vast  circulation  this  work  has  had  in  Europe,  where  it  has  already  been 
reprinted  in  four  or  five  languages,  not  to  speak  of  the  numerous  German  edi- 
tions, of  which  SEVEN  have  been  published,  speaks  loudly  in  favor  of  its  in- 
trinsic merit  without  which  such  a  celebrity  could  never  have  been  attained. 
To  every  n^n  engaged  in  public  business,  who  needs  a  correct  and  ample  book 
of  reference  on  various  topics  of  science  and  letters,  the  Encyclopedia  Ameri- 
cana will  be  almost  invaluable,  lo  individuals  obliged  to  goto  situation* 
where  books  are  neither  numerous  nor  easily  procured,  the  rich  contents  of" 
these  twelve  volumes  will  prove  a  mine  which  will  amply  repay  its  purchaser, 
and  be  with  difficulty  exhausted,  and  we  recommend  it  to  their  patronage  in 
the  full  conviction  of  its  worth.  Indeed  it  is  difficult  to  say  to  what  class  of 
readers  such  a  book  would  not  prove  useful,  nay,  almost  indispensable,  sinc« 
it  combines  a  great  amount  of  valuable  matter  in  small  compass,  and  at  mode- 
rate expense,  and  is  in  every  respect  well  suited  to  augment  the  reader's  stock 
of  ideas,  and  powers  of  conversation,  without  severely  taxing  time  or  fatiguing 
attention.  These,  at  least,  are  our  contusions  after  a  close  and  candid  ex- 
amination of  the  first  volume. — Am.  D^ttLMvcrtiser. 

We  have  seen  and  carefully  examined  t|fc  first  volume  of  the  Encyclopaedia 
Americana,  just  published  by  Carey,  Lea  ma  Carey,  and  think  our  readers  may 
be  congratulated  upon  the  opportunity  of  making  such  a  valuable  accession  to 
their  libraries. — Aurora. 

The  department  of  American  Biography,  a  subject  of  which  it  should  be 
disgraceful  to  be  ignorant,  to  the  degree  that  many  are,  is,  in  this  work,  a 
prominent  feature,  and  has  received  the  attention  of  one  of  the  most  indefati- 
gable writers  in  this  department  of  literature,  which  the  present  age  can  fur- 
nish.— Boston  Courier. 

According  to  the  plan  of  Dr.  Lieber,  a  desideratum  will  be  supplied ;  the  snb- 
stance  of  contemporary  knowledge  will  be  brought  within  a  small  compass; — 
and  the  character  and  uses  of  a  manual  will  be  imparted  to  a  kind  of  publica- 
tion heretofore  reserved,  on  strong  shelves,  for  occasional  reference.  By  those 
who  understand  the  German  language,  the  Conversation  Lexicon  is  consulted 
ten  times  for  one  application  to  any  English  Encyclopaedia.— National  Gaz. 

The  volume  now  published  is  not  only  highly  honorable  to  the  taste,  ability 
and  industry  of  its  editors  and  publishers,  but  furnishes  a  proud  sample  of  the 
accuracy  and  elegance,  with  which  the  most  elaborate  and  important  literary 
enterprises  may  now  be  accomplished  in  our  country.  Of  the  manner  in  which 
the  editors  have  thus  far  completed  their  task,  it  it  impossible,  in  the  course  of 
a  brief  newspaper  article,  to  speak  with  adequate  justice. — Boston  Bulletin. 

We  have  looked  at  the  contents,  generally,  of  the  second  volume  of  this 
work,  and  think  it  merits  the  encomiums  which  have  been  bestowed  OB  it  in 
the  northern  papers.  It  continues  to  be  particularly  rich  in  the  departments 
of  Biography  and  Natural  History.  When  we  look  at  the  large  mass  of  mis- 
cellaneous knowledge  spread  before  the  reader,  in  a  form  which  has  never  been 
equalled  for  its  condensation,  and  conveyed  in  a  style  that,  cdnnot  be  surpassed 
for  propriety  and  perspicuity,  we  cannot  but  think  that  the  American  Ency- 
clopedia deserves  a  place  in  every  collection,  in  which  works  of  reference  form 
a  portion."— Southern  Patriot. 


